We express our gratitude to the organiser of the conference on the archaeology of Bahrain and its surrounding regions for giving us an opportunity to present our projects in Bahrain. We are also grateful to the Bahrain Authority for Culture and Antiquities, especially H.E. Shaikh Khalifa Al-Khalifa, the present President of the organisation, H.E. Shaikha Mai Bint Mohammed Al-Khalifa, the former President of the organisation, Dr Salman Almahari, the Director of Department of Archaeology and Museums, and Dr Pierre Lombard, the Superintendent of Archaeology of the organisation, for their generous support to our projects.

I. Introduction

1The Japanese Archaeological Mission to Bahrain conducted field work in the late 1980s and the early 1990s under the directorship of Masatoshi Konishi and Takeshi Gotoh (Konishi et al., 1994, 1995a, 1995b). In this first mission, the Japanese team excavated a few burial mounds of the Early Dilmun period at Bûrî and a temple site at Ain Umm Es-Sujjur. Especially at the latter site, the team expanded the trench dug by the Danish team and exposed two wells, an integral part of the temple complex. With a gap of 20 years, the Japanese team led by Takeshi Gotoh resumed its campaign in Bahrain in 2015, focusing on the Early Dilmun burial mound site of Wâdî Al-Sail. With generous permission and support from the Bahrain Authority for Culture and Antiquities, this excavation project continues the work at the site till now.

2In addition to the excavation project, the Japanese mission commenced in 2020 a survey project using a UAV (Unmanned Aerial Vehicle, drone) and the 3D modelling technology (Structure from Motion = SfM) of preserved burial mound sites of the Early Dilmun period, which is called the Dilmun Mapping Project. This project conducted three seasons' campaigns and completed the mapping of mounds at A'alî, Saar, Janabîyah, Al-Maqsha, Wâdî Al-Sail, Bûrî, Karzakkân, and Dâr Kulayb (Figure 1(a)). This project has enriched our understanding of large-scale burial mound sites of the Early Dilmun period.

3This paper overviews the results of these two projects conducted by the Japanese team.

II. The Early Dilmun Period

4The Early Dilmun Period is divided into two phases: the Early phase and the Late phase (Lowe, 1986; Frohlich, 1986).

5The Early phase dates from 2300 BCE to 2050 BCE. Before the Early Dilmun Period, Bahrain was sparsely populated; however, during the Early phase of the Early Dilmun Period, large-scale immigration into Bahrain took place. The immigrants created villages and began the construction of burial mounds However, maritime trade was dominated by Mesopotamian polities, and Dilmun still played a minor role in maritime trade during the Early phase (Abe and Uesugi, 2021; Højlund, 2007; Laursen, 2017; Laursen and Steinkeller, 2017, Olijdam, 2016).

6The Late phase dates from 2050 BCE to 1700 BCE. During the Late phase, Dilmun dominated maritime trade, linking Mesopotamia, Oman and Indus. Consequently, Dilmun society rapidly developed, and a walled town, large public temples, and gigantic royal tombs were constructed during the Late phase. However, Dilmun society suddenly collapsed around 1700 BCE for unknown reasons (Højlund, 2007; Laursen, 2017; Laursen and Steinkeller, 2017).

III. Dilmun Mapping Project

7While the Early Dilmun landscape, composed of a great number of burial mounds, had been more or less preserved until the 1970s, the modern town planning projects since the 1970s considerably changed the landscape. The hilly part of the Bahrain island, which, historically speaking, had been more or less useless for habitation, was selected for construction projects of modern housing. A number of rescue excavation projects were undertaken by archaeologists from different countries to document burial mounds before their destruction and provided invaluable information regarding Early Dilmun burial mounds; however, most of the rescue excavations have not been published in detail, making it difficult to integrate the data to our multi-faceted examination of burial mounds.

8In this circumstance, Steffen Terp Laursen's work using aerial photos from the British Air Force survey in 1959 to map the original distribution of burial mounds is highly important, as this work made it possible to overview the entire distribution of burial mounds (Laursen, 2008). Based on his work, Laursen counted about 75,000 burial mounds of the Early Dilmun period, of which 28,000 were classified as belonging to the Early phase (c. 2300-2000 BCE) and 47,000 to the Late phase (2000-1700 BCE). Furthermore, he made discussions on the developments of burial mound sites, especially of A'alî and Karzakkân, to see dynamic changes in the socio-political landscape in the Early Dilmun society (Laursen, 2008, 2010). While Eric Olijdam discusses the development of Early Dilmun polities in a different way (Olijdam, 2016), the current discussions on the developments of burial mound sites are basically based on Laursen's map.

9However, Laursen's map entails some problems. Since the photos taken by the British Air Force are not high in resolution, it is difficult to identify the morphological features of many mounds, though not all. Classifying mounds into the Rifa'a or Early type and the Bârbâr or Late type based on the mound configurations, which reflect different types of burial chambers (Lowe, 1986; Frohlich, 1986) cannot be straightforward. Besides, the lack of altitude data in the aerial photos also renders it difficult to make a dimensional examination of mounds.

10A mission was set up in 2020 by Akinori Uesugi in collaboration with the Bahrain Authority for Culture and Antiquities to conduct a mapping project using a UAV and 3D modelling technology in order to document preserved mounds, considering these issues. Compared to the photos taken by the British Air Force, the areas of currently preserved burial mound sites have been diminished by modern buildings; however, the detailed documentation of preserved mound sites, which still have considerable extent including thousands of mounds, was considered to be urgent and essential for the Early Dilmun burial mound studies. It supplements Laursen's map and enables spatial analysis of the mortuary landscape of the period.

11Thousands of photos taken by a UAV for each site along with more than 10 GCPs (Ground control points) that were georeferenced with RTK GNSS were processed using Metashape Pro (AgiSoft) to create a 3D model, which was exported as a DEM (Digital Elevation Model) to be used in GIS software (Arc GIS, Esri). The resolution of models is less than 2.0 cm per pixel. A slope model and contour lines were created to identify burial mounds. The maps created by this method were used for qualitative and quantitative analyses of burial mounds. The morphological features of burial mounds were visually and statistically examined. As a result, the dynamic process of the formation of burial mound sites has been revealed.

12As Figure 2 shows, the basal diameter (BD), top diameter (TD) and relative height (H) were measured using Arc GIS for each of the identified mounds from the DEM, and the volume was calculated. An index calculated by BD/TD indicates the ratio between BD and TD, which can be used for identifying the mound morphology. The index was categorised to show the variation of the mound morphology. These categories help quantitatively classify mounds into the Rifa'a type and the Bârbâr type; for the mound morphology, the mounds of Categories 1 and 2 with wider flat tops can be classified as the Rifa’a type, as they are dominant at Wâdî Al-Sail of the Early phase, and the mounds of Categories 3-11 that are increased at the sites of the Late phase can be grouped as the Bârbâr type. The categorised index of the volume also helps see the distribution of the different sizes of mounds.

1. Wâdî Al-Sail

13The northern part of the site of Wâdî Al-Sail (Figure 1(b)), which belongs to the Early phase of the Early Dilmun period (this chronological affiliation can be determined by the mound shape and some ¹⁴C dates from excavations), is comprised of 301 burial mounds, including subsidiary mounds on the eastern side of the wâdî (Figure 3). This number excludes a dozen of mounds preserved in a small area on the western side of the wâdî. The southern part of the site is not accessible for the survey as it is located in the military area. The mounds in this area were identified and mapped using a high-resolution satellite image (Figure 3). All of the burial mounds have a low mound with a flat top, which has been identified as the Rifa'a type of Lowe's terminology (Lowe, 1986) (also termed the Early type by Frohlich (1986)). The distribution of burial mounds is considerably sparse across undulated and sloped terrain. Larger mounds tend to be located at higher levels of the slope, as noticed by the Danish team (Højlund et al. 2008). While the linear arrangement of several mounds along a slope was noticed in the case of a narrow ridge, the curvilinear arrangement of mounds across a wider slope was identified at different levels of a slope. Also, in the latter case, the highest position of the slope was occupied by a group of larger mounds, while the groups at the lower levels were composed of smaller mounds. In this case, it can be pointed out that multiple groups of mounds arranged in a curvilinear line were stratified in size depending on the altitude. It likely signifies that a wider slope was used by a larger social group that was socially stratified, in contrast to smaller groups of mounds vertically arranged along a narrow ridge.

2. A'alî

14The site of A'alî, located to the north of Wâdî Al-Sail, has been known to represent the burial mound sites of the Late phase of the Early Dilmun period (c. 2000-1700 BCE) (Figure 4(a)). This site has many features different from those of Wâdî Al-Sail; the site is situated on a gentle slope without any deep gullies on the terrain; more than 4,800 mounds are continuously spread over the slope; the Bârbâr type or the Late type of mounds (Lowe, 1986; Frohlich, 1986), which are distinctly higher than the Rifa'a type, are included at this site; large-scale burial mounds called Royal Mounds are present in the northeast corner of this site.

A/ The preponderance of the Rifa'a type

15As a result of our survey, the features listed above were visually confirmed, but the metrical and quantitative analysis of mounds based on the data from our survey has exhibited that 80 % of mounds at this site belong to the Rifa'a type with a wide flat top and a low profile (Figure 4(a), 4(c)). However, the Rifa'a-type mounds at A'alî are noticeably larger than those of Wâdî Al-sail. It likely indicates that mounds became larger at the very end of the Early phase or the very beginning of the Late phase when the distribution of burial mounds was shifted to the outer slope of the hilly terrain of the Bahrain Dome. Most of the central part of Area 2 of A'alî was found to be occupied by enlarged Rifa'a mounds, and Bârbâr-type mounds were considerably limited in number.

B/ Distribution pattern of small-to-large mounds in the large cluster of Area 2

16It is worth noting that large mounds of the Rifa'a type (Volume Categories 6 and 7) are scattered with some distance from each other and surrounded by smaller mounds of the Rifa'a and Bârbâr types in the central part of Area 2 of the site (Figure 4(c)). It suggests that large mounds of the Rifa’a type were first built, followed by smaller mounds surrounding the formers. The repetition of this process may have led to the formation of the highly dense area of the central part of the site. Most of the central part of Area 2 was occupied by Rifa'a-type mounds (Mound Types 1 and 2), while mounds of the Bârbâr type were considerably limited in number as there was no space left by the time of the development of the Bârbâr type.

C/ Distribution pattern of extra-large burial mounds

17Extra-large burial mounds (Volume Categories 8-10) tend to be distributed in the Royal Mound area (Area 1), the northern edge of Area 2, and the northern half of Area 3 (Figure 4(b), 4(c)). There are several distribution patterns of extra-large mounds, each of which is distinct from each other.

18In the Royal Mound area (Area 1), which is in the northeastern corner of the site, extra-large burial mounds were built with a clear-cut principle unique to this area (Laursen, 2017)(Figure 4(b)). The pattern seems to symbolise some ideology. The construction of extra-large mounds seems to have started with Mound Type 2 in the northeastern corner of the area and continued to Mound Type 4. It is likely that the overall distribution pattern of mounds was planned at the time of the construction of the first mound in this area and was followed until the later phase.

19The second type of the distribution pattern of extra-large mounds is the linear arrangement. In the northwestern corner of Area 2, there is a cluster of extra-large and large mounds aligned in a straight line (Figure 4(c)). Mounds were constructed close to each other, showing a lineage of persons buried in these mounds. The first ones were built at the time of Mound Type 1, and mounds were continuously constructed until Mound Type 3.

20The third type is the irregular clustering of mounds. This pattern can be found in Area 3. Several larger mounds were built close to each other without any clear-cut arrangement (Figure 4(d)). In the northwestern corner of the area, an extra-large mound of Mound Type 1 (Volume Category 9) was built, followed by the continuous construction of extra-large and large mound of Mound Types 2 to 4. Another cluster of this type can be found in the southwestern corner. It is composed of four mounds. An extra-large mound (Volume Category 8) was first built, followed by two mounds of Mound Type 2 (Volume Category 7) and a mound of Mound Type 3 (Volume Category 6). This cluster is strangely located away from the main part of the area.

21The fourth type is the extra-large and large mounds with an outer ring wall, which has been considered the mounds of social elites (Højlund et al., 2008; Laursen, 2008). This mound type can be found in the northern parts of Areas 2 and 3 (Figure 4(c), 4(d)). Especially in Area 3, several mounds with an outer ring wall are located relatively close to each other (Figure 4(d)). Because of the presence of outer ring walls, no smaller mounds are situated around these ones. Compared to the second and third types, these mounds encircled by an outer ring wall are outstandingly exceptional. As was seen in the distribution pattern of small-to-large mounds in the central part of Area 2, a large mound tends to be the centre of a cluster. A large mound built first was surrounded by smaller mounds of later phases. It is a principle of the spatial arrangement of mounds in this area. The second and third types also follow this principle; however, this fourth type prohibits the subsequent construction of mounds around the mound by building the outer ring wall. While the theory that they represented burial mounds of highly ranked persons may explain their exceptionality, the fact that they are exceeded in size by the mounds of the second and third types. The mounds with an outer ring wall in Area 3 belong to Volume Categories 6 and 7, while the mounds of the second and third types include extra-large mounds (Volume Categories 8-10) (Figure 4(d)). There seems to be some social background behind the mounds with the outer ring wall other than the social rank of the persons buried.

D/ The increase of complexity in the mound configuration

22As is briefly overviewed above, the burial mound configuration, such as location, density, area and distribution pattern, considerably differs between the Early and Late phases of the Early Dilmun period. The mounds of the Early phase were built in a scattered pattern on relatively steep slopes along the watercourse of Wâdî Al-Sail. Narrow ridges facing the wâdî were occupied by several mounds representing smaller social groups. Even on relatively wider slopes, the distribution of mounds is in a scattered fashion, while many more mounds were built in a complex pattern, suggesting some more complex social hierarchy compared to the small clusters of mounds on narrow ridges. The mounds are noticeably smaller than those of the Late phase, while a modest hierarchy in size can be observed.

23Flat and gentle slopes were selected for the burial mounds during the Late phase. As a result, the distribution of mounds became extraordinarily dense, and the size of the cemetery greatly expanded. Consequently, distribution patterns or principles different from those of the Early phase were introduced, making the composition of burial mounds more diverse and complex. The presence of extra-large mounds, the widened hierarchy in size, the different distribution patterns in different parts of the cemetery, and so on, all suggest the complex process of the formation of an extensive cemetery. Furthermore, the continuous development of a cemetery by the Rifa'a and Bârbâr types also provides another dimension to the complexity of the cemetery formation.

24Although they were not described in this paper, the other burial mound sites, Karzakkân, Dâr Kulayb, Saar, Janabiyah, and Buri, also present a complex process of the development of the cemetery. Further works are needed to better understand the complexity of the extensive cemetery of the Early Dilmun period and the social transformation of the Early Dilmun society.

IV. The Wâdî Al-Sail Archaeological Project

25The second half of this paper introduces the results of another Japanese project, Wâdî Al-Sail Archaeological Project (Gotoh et al., 2020; Abe and Uesugi, 2021). Wâdî Al-Sail is one of the Early Dilmun burial mound fields in Bahrain and an extremely important site to consider the origins of Dilmun.

26First Wâdî Al-Sail burial mound field is introduced and then the authors consider the origins of Dilmun by comparing Wâdî Al-Sail and burial traditions in neighbouring regions.

1. Burial mounds at Wâdî Al-Sail

27In the Early Dilmun Period, approximately 75,000 burial mounds were constructed in Bahrain. Figure 1(a) shows the distribution of burial mounds in the 1950s. Purple lines show the distribution of burial mounds of the Late phase while blue lines show the distribution of burial mounds of the Early phase (LAURSEN, 2008). Burial mounds of the Early phase used to be widely distributed. However, most of these have been lost because of recent urban developments. Currently, burial mounds of the Early phase remain only around Wâdî Al-Sail (Højlund et al., 2008; Laursen, 2008).

28Wâdî Al-Sail is a 4km long wâdî running from southeast to northwest on the inland plateau of Bahrain (Figure 1(b)). Along the upper stream of this wâdî, hundreds of burial mounds are thinly scattered on both slopes of the wâdî (Figure 5(a)). The low density of the burial mounds is one of the characteristics of burial mounds of the Early phase.

29Since Wâdî Al-Sail is very large, our research focuses on its northeastern part (Figure 3). This area measures 900m by 400m. Even in this area, there are approximately 300 burial mounds. Blue circles represent the burial mounds. In 2014, we started our project and have excavated 46 burial mounds in 8 excavation seasons.

30The burial Mounds at Wâdî Al-Sail were made of stones. Initially, an oval burial chamber and an outer wall were constructed, followed by filling the space between them with cobbles (Figure 5(b)).

31The long axis of a burial chamber is usually east-west (Figure 5(c)). One person was buried in one burial mound. The dead was usually buried in a crouching position facing north; the head was usually pointed eastward. Partially burnt sheep/goat’s bones are often found in front of the knee of the skeleton. They are usually sooted. This strongly suggests grilled sheep/goat’s meat was placed in the chamber.

32Typical grave goods include faience beads and carnelian beads imported from Indus and pottery from Oman and Mesopotamia. It is generally believed that jars from Mesopotamia originally contained perfume oils. Shells containing cosmetic pigments are also often found.

33Compared to the Late phase, the hierarchy of burial mounds was less developed during the Early phase; nevertheless, some degree of hierarchy is evident. The burial mounds at Wâdî Al-Sail can be divided into three types; ordinary burial mounds, large burial mounds and ring burial mounds.

34Most of the burial mounds at Wâdî Al-Sail can be categorized into the ordinary burial mounds (Figure 5(b)). The ordinary burial mounds are small and range between 5m and 7m in diameter.

35Of approximately 270 burial mounds, three are larger than 10m in diameter (Figure 5(d)). Ordinary burial mounds and large burial mounds are situated in different places; ordinary ones are located on the slope of the wâdî, whereas large ones are placed on the top of the slope which offers a good view of the wâdî.

36One of the large burial mounds is even encircled by a ring wall. This mound was excavated by the Danish team. Such mounds are called “ring burial mounds”. The ring burial mounds are considered the burials of incipient Dilmun leaders (Figure 5(e)) (Højlund et al., 2008; Laursen, 2008).

2. Wâdî Al-Sail and the Origins of Dilmun

37Wâdî Al-Sail is an extremely important site for considering the origins of Dilmun. As discussed above, Bahrain was sparsely populated before the Early Dilmun period and during the Early phase of Early Dilmun period, large immigration to Bahrain took place. The settlers created villages in Bahrain and began to construct burial mounds, creating the burial mound field of Wâdî Al-Sail.

38Where did these people come from? Some argue that they were from the Oman Peninsula whereas others contend that they were from Tarut Island (e.g. Gotoh, 2015; Potts, 2010). However, both these origins are unacceptable because burial traditions in Tarut Island and the Oman Peninsula are completely different from those in Bahrain.

39Wâdî Al-Sail provides an important clue for answering this question. Cairn fields, which are very similar to Wâdî Al-Sail, are widely distributed across Syrian desert, northern part of Arabian desert, the Negev and the Sinai (Fujii, 2006; Steimer-Herbet, 2004). As no permanent settlements are known near most of the cairn fields, it is generally assumed that the cairns were burials of pastoral nomads (Ilan, 2002; Rosen, 2008).

40Although the majority of these cairn fields have been dated to between 4th Millennium BCE and 3rd Millennium BCE, recent studies have generated some dates as old as 6000 BCE (e.g. Abu-Azizeh et al., 2004; Bonacossi and Iamoni, 2012; Iamoni, 2014).

41The construction method of cairns in these fields are very similar to Wâdî Al-Sail. Two cairn fields are introduced here as representative examples. The cairn field of Nahal Mitnan is one of the largest cairn fields in the Negev. This cairn field is dated to 4th-3rd millennium BCE and consist of approximately 250 cairns (Haimann, 1993). In the cairn field, most of the cairns are from 5 to 7m in diameter. The cairn has an oblong stone chamber in its center and an outer wall surround it. The space between the stone chamber and outer wall are filled with stones. The long axis of the stone chamber is basically east-west.

42Talat Ubayda is a cairn field located in the Jafr Basin in southern Jordan and dated to 4th-3rd millennium BCE. Approximately 30 cairns are linearly distributed along a cliff. This site was excavated by Kanazawa University in Japan and one of the authors joined the excavations. The cairn at Talat Ubayda is composed of stones and has an oblong burial chamber in the centre. It is surrounded by an outer wall and the space between them is filled with cobbles. Even the long axis of the stone chamber is east-west (Figure 5(f)) (FUJII, 2013). Other cairns fields also show similarities to Wâdî Al- Sail in the construction method although there are exceptions.

43A three-tiered hierarchy consisting of ordinary burial mounds, large burial mounds and ring burial mounds can also be seen in these cairn fields. For example, a similar three-tiered hierarchy is reported in Mount Bishri in Syria. At Tar al-Sbai in Mount Bishri, several hundred cairns are linearly distributed along a large cliff. The cairns are dated to 5th to 3rd millennium BCE. According to the Finnish excavation team, ordinary cairns are from 2.6m to 5m in diameter. But there are a few large cairns that are over 10m in diameter and some of the large cairns have a ring around them. M. Lönnqvist argue that the ring cairns are burials of tribal leaders of pastoral nomads (Lönnqvist, 2006, 2010).

44The cairn field of Jebel Abyad is located to the northwest of Palmyra in Syria and dated to the late 3rd millennium BCE and the early 2nd millennium BCE. According to T. P. Schou, the cairns can be divided into ordinary cairns whose diameter is less than 9m and large cairns, which is larger than 9m in diameter. In addition, large cairns are rare and located in prominent locations such as the top of a hill. Furthermore, some of the large cairns even have a ring around them (Anfinset and Meyer, 2010; Schou, 2014).

45In addition, ring burial mounds are also widely distributed in the Syrian desert and northern part of Arabian deserts (e.g. Laursen 2008). One cairn field is introduced here as an example. In Palmyra, Syria, three ring cairns were recently discovered at the top of Jabal Mohammad Ibn Ali, located 10km to the north of the Palmyra Oasis although they have not been excavated yet. These ring burial cairns are placed alone on the hill top and so command good views of the Palmyra Oasis. These ring burial mounds are large and the mounds are over 10m in diameter. Their special location and large size suggest that these are burials of pastoral nomad leaders, who probably controlled the region near Palmyra (Iamoni, 2014).

46The similarities between Wâdî Al-Sail and the cairn fields in Syrian desert, northern part of Arabian desert, the Negev and the Sinai suggest the Dilmunites probably originated from amongst the pastoral nomads who dwelt in these arid regions.

47Additional archaeological evidence is also available. Rock art in these arid regions often depicts Bronze Age pastoral nomads. They have unique daggers. The pommel of the dagger is lunate shaped (Newton and Zarins, 2000). It is noteworthy that daggers excavated from burial mounds in Bahrain are very similar to the daggers depicted in the rock art (Figure 5(g)). This similarity also demonstrates a strong connection between Dilmunites and pastoral nomads.

48Furthermore, strong evidence has recently been discovered. The Bahrain team excavated one of the Dilmun royal mounds of the Late phase, and Dr. Laursen accidentally discovered fragments of stone vessels. On three fragments, a Dilmun royal name was inscribed. This was the first discovery of Dilmun royal name from royal mounds. The king was named Yagil-El. This is an important discovery because Yagil-El is a typical Amorite name (Laursen, 2017). Furthermore, a Mesopotamian text from Lagash also says that Dilmun is the land of the Amorites and an Amorite “town” is situated in Dilmun (Laursen and Steinkeller, 2017).

49Amorites are pastoral nomadic groups mentioned in the ancient Mesopotamian texts. Although it is assumed that they originally inhabited in the Syrian desert to the west of Mesopotamia, they left the desert and infiltrated southern Mesopotamia in the late third millennium BCE. In the early 2nd millennium BC, the Amorites seized power and established their own dynasties in major cities, such as Babylon, Uruk, and Larsa in southern Mesopotamia.

50The evidence from Wâdî Al-Sail and other sources strongly suggests that Dilmun people originated from pastoral nomads, probably called Amorites.

V. Summary

51The research on Early Dilmun burial mounds in Bahrain has a history of more than 100 years. Many missions from Bahrain and different foreign countries conducted excavations on burial mounds, yielding a great amount of data and information on burial mounds. Many attempts have been made to approach different aspects of the Early Dilmun society based on the evidence from burial mounds. However, very few information regarding mound morphology, burial chamber, human remains, burial goods, and so on, has been published for many mounds, making it difficult to develop multifaceted approach to the mortuary practice and its significance to the Early Dilmun society.

52What is the most important for the Early Dilmun burial mound studies is to create and share the basic data set of burial mounds. The Dilmun Mapping Project conducted extensive surveys on the burial mound sites, currently preserved as the World Heritage. It has created a new data set for the spatial distribution of burial mounds of the Early Dilmun period.

53The Wâdî Al-Sail Archaeological Project has been revealing the mortuary and burial practice of the Early phase of the Early Dilmun period, which was not well documented and studied before. Wâdî Al-Sail provides an important clue for considering the origins of Dilmun.