The Western Bilsk hillfort is situated on a plateau between the Vorskla and Sukha Grun rivers, on the high banks of the latter. Its modern surface is covered with ash hills that could be seen as kurgan-like mounds with slightly lighter soil. Archaeological excavation of ash hill 5 has been carried out since 1998. In the year 2004, two excavation sites were dug out in its periphery. The southern excavation site measured 64 m2. The stratigraphy of the ash hill is the following: up to 30 cm – ploughing layer; 30-80 cm – cultural layer; 80-120 cm – clear black soil; below 120 cm – yellow clay. Four household pits were explored here; they were filled with ashy soil containing pieces of charcoal, pottery and animal bones. Pit 23 was distinguished by a find of a large storage jar and a fragment of a late 6th – early 5th c. BC Chios amphora. Besides that, a pin and an arrowhead date by the 5th c. BC was found here. Pit 25 was filled with burnt clay and stones, as well as fragments of pottery that probably were dumped from a hearth. An unusual handmade pot with two handles could be considered as a copy of a Greek amphora. Fragments of a Samos and Klazomenai amphorae from this pit date by the second half of the 6th c. BC. The western excavation site measured 57 m2. The stratigraphy of the ash hill is the following: up to 35 cm – ploughing layer; 35-90 cm – cultural layer filled with a large amount of ash. Two household pits were explored here. The sacrifice of a goat and a bear skull was found in one of them (No 26). Black-glazed handmade pottery could be seen at this part of ash hill. However, Greek amphorae fragments belong to the 6th c. BC. Numerous artefacts were obtained from the cultural layer. Typical decoration of the pot’s rims are pricks and raised punctured borders. Storage jars and ladles are present in smaller amounts. Among the bone finds, one should mention tools for leather currying, pipes and polisher. Greek vessels are also present in the layer: fragments of Chios, Thasos, Lesbos and Klazomenai amphorae and a black-glazed kylix of the late 6th – early 5th c. BC. Metal artefacts are numerous and point to diversified crafts in the life of the local population. One can mention a hand drill, different types of knives, a needle, an awl, plates for a scale armour, pieces of a horse bridle, a fragment of a bronze cauldron and drops of bronze. Notable adornments are the pins and boar fang pendant.

The investigation of theash mound 13 started in August, 2005. 297 m2 area was excavated. There were found five kitchen pits and an above-ground building. A hemispherical ash mound was createdd 60 m in diameter. An occupation layer rich in grey ash was found at 0.2 – 0.7 m depth. A light (almost white) spot of almost 16 m² was found in the south-eastern part of the excavation at 0.25 m depth, under which was a layer of orange clay grit (probably the remains of the walls and floor of the above-ground building). There was a small oval pit 0.6 × 1.1 m in diameter and 0.6 m deep in the western part of the building. There was a layer of stones under the clay floor, some of which were set on edge and outlined the external line of the walls. A layer of stones was observed, as well as, fragments of grain mills and large fragments of ceramics under the floor in the eastern part. A bright organge layer of burnt soil .1 metre deep lay under the stones in both parts of the buiding. The kitchen pit (a cellar) was situated on the south-west from the building. It was of an oval shape 2.1× 3.3 m in size. There was an entrance, stairs and 0.4 m wide shelf carved in continental clay. The filling of the cellar lay0.5 – 0.6 m below the modern surface. The general depth of the household assemblage was 2.9 – 3 m. The excavators note that one of the peculiarities of the building was that after it had ceased to be used as a household it was used for ceremonies. Eight almost complete skeletons of dogs with signs of violent death were found along with a large amount of the pottery fragments and other animal bones in the pit. The deadanimals were put on the bottom of the cellar. A human cranium was also found, as well asburnt bones of a dog and the so called clay “loaves” that proved that the pit was used for ceremonies. Among the goods found in the excavation was a great amount of local pottery fragments (fragments of the pots’ lips with open holes with finger-impressed moldings at the edge, bowls with bent edges, wine amphorae and ladles). Bone objects such as a recut astragal, an adz, borers and tubes were also found. A specific feature of these tools was a polished surface. Antique imported pottery was represented by numerous fragments of ancient amphorae. Among these fragments are parts of rims, walls, handles and feet of commercial amphorae from Chios, Klazomenai, Thassos, and Lesbos. Some fragments of Miletus amphorae’s rims were found. There were alsofragments of the walls, handles and rims of the Greek painted pottery, some of which were covered with black glaze. Iron goods that occur quite often were represented by knives with tangs for wooden handles, nail-shaped pins, single iron bar knife, and chain mail plates. There were also arrowheads and pins made of bronze, and fragments of bronze cauldrons. Judging from the types of the pottery, imported goods and metal objects found in the occupation layer and assemblages of the excavation in 2005 it may preliminary belong to the end of the 6th century BC.

Two objects were explored during the season 2007. First is ash hill 30 situated on the western periphery of the hillfort not far from the rampart. The explored area at the site measured 115m2. The southern part of ash hill 30 was covered with mixed soil that was dumped in the Early Modern period when the Cossacks used to mine saltpetre at the hillfort's rampart. Thanks to that, numerous materials survived within the cultural layers below. Handmade pottery, mostly pots bowls and storage jars constituted the majority of the finds. Other tools of everyday life are knives, pins, arrowheads, etc. Besides that, more than two thousand animal bones were detected here. A big pit-house detected at the ancient buried surface was also explored here. It was a circle construction 5.25 m in diameter and 0.8 m deep. Two additional pits (cellars?) up to 0.8 m deep were placed at the NE and S corners of the basement. The dwelling was filled with ashy soil containing a lot of pottery shreds and Greek wares dated by the 6th c. BC. Exploration at ash hill 13 were held since 2005. After the geophysics surveys, a trench measured 217 m2 was dug out at the S sector of the ash hill. Remnants of a dwelling and five non-simultaneous household pits were explored here. The dwelling measured 4.5 × 5.5 m. It was distinguished by two scattered Klazomenai amphorae dated by the early 6th c. BC that laid on the clay floor together with numerous fragments of storage jars. Also, a lot of the local wares fragments were detected within the mentioned objects. Besides that, a stone base of the altar with part of the clay floor was found near the dwelling. Similar religious structures were typical for the local farmsteads of the 6th c. BC.

Ash hill 13. It had been explored since 2005 and this year excavating trenches measured 144 m2 were dug out on the northern sector of the mound where four household pits and an altar with the remnants of the sacrificial animals were explored. The altar was constructed in a form of a circle 0.8 m in diameter using burned clay. Additionally, its surface was covered with a thin layer of white clay. Fragments of another broken altar were found dumped at the bottom of pit 8. An interesting object is a pit 10 3.4 m deep. Numerous fragments of the Greek amphorae and storage jars were deposited in it at the level 1.6 m deep. Besides that, a horn tip of the bow ornamented in the Scythian animal style was laid at the bottom of the pit. Interesting, that the images were not finished and the tip had no traces of usage. Apart from the mentioned complexes, a big anomaly that was detected during the previous geophysics surveys was partly examined by the archaeologists. It has appeared that it is a big object (dwelling 4) covered with a dumped burned clay. Interesting clay lamp with three legs could be mentioned among the other finds, such as handmade pots and luxurious black-glazes table wares. But the most fascinating finds are the dogs' skeletons discovered in this object at the level 2.4-2.65 m. One of the killed dogs had a necklace made of miniature beads that lay around its cervical vertebrae. A cowrie shell was found near the skull of the other dog. Besides the local products, a lot of fragments of the Greek amphorae was found on the ash hill 13. Also, a single fragment of the painted oenochoe dated by the late 7th – early 6th c. BC could be mentioned. Ash hill 10. An excavating trench measured 237 m2 was dug out at the western part of the ash hill. A big pit-house measured 7 × 4.5 m was discovered at the southern part of the excavation site. It was filled with ashy soil mixed with layers of charcoal and ash as well as a lot of pottery fragments were deposited within. Besides the pit house, five household pits were explored here. Some of the table wares from the objects were ornamented with a carved geometric ornament filled with white paste. Fragments of the Greek amphorae oenochoe are dated by the late 7th – early 6th c. BC. The most interesting imported find is the Olbian coin in form of a dolphin.

The central part of ash hill 10 was explored during the season of 2009. Two dwellings, several household pits, remnants of one altar and 26 sacrificial animals were explored within the trench measured 210 m2. Northern dwelling measured 9.2 × 6 m and up to 2 m deep. Its construction was supplemented with an additional pit 0.3 m deep that was placed in the separate household niche in the southern wall. 35 postholes for the wooden frame were detected alongside the walls. The entrance was traced as a step dugout in the northern wall. The eastern corner of the house is distinguished by numerous small postholes up to 2 cm in diameter. Fragments of several human skulls and numerous animal bones that can be considered as sacrificial ones were deposited within this object. The majority of the collected artefacts consist of handmade pottery. Besides that, a carved horn psalia, bronze arrowheads and adornments, iron pins, needles and knives could be mentioned. Most of the amphorae fragments as well as painted pottery dated by the mid. 6th c. BC. The southern dwelling was explored not to a full extent. However, the researchers trace its measures 9.95 × 8.25 m and 1.8 m deep. The wooden construction of the hut was fixed in the 26 postholes up to 20 cm in diameter. The lower part of the dwelling was filled with mixed layers of black soil and clay. Its upper part was filled with a layer of ash 1 m thick. The most distinguished finds from this complex are the horn psalia, Greek table wares, bronze arrowheads, pins and a bracelet. All the artefacts are dated by the late 7th – early 6th c. BC. Remnants of the altar were traced not far from the Northern dwelling. It was the layer of burned soil on which researchers discovered broken parts of the clay construction with a smooth surface. More than 20 thousand animal bones were collected during excavation on the ash hill 10. According to analyses, the majority of the sacrificial bones belonged to dogs, pigs and small cattle.

During the season 2010, the researchers worked on ash hill 13 uncovering 168 m2 on the excavation site. The first task was completing the exploration of dwelling 4. Half of this object was excavated earlier, in 2008. After the end of the works, it has appeared that it was an oval pit-house measured 7.5 × 6 m and 2 m deep. An additional household pit 0.8 m deep was dug out in the southern corner within the object. The wooden frame was fixed in the six postholes. The majority of the collected artefacts consist of handmade pottery. The most noticeable find was a dog skeleton with a necklace explored yet in 2007. Besides the dwelling, four household pits were explored in 2010. A broken clay altar together with fragments of the painted oenochoe was deposited in one of the pits. Pit 11 measured 2.8 × 3 m and 3.4 m deep was distinguished by a huge amount of the burned clay fragments many of which had prints of a wooden frame. Those fragments covered the lower layer of the pit where a lot of Greek pottery fragments survived. It was the shreds of 13 Klazomenai amphorae and one of Miletus amphora dated by the first half of the 6th c. BC. Pit 14 and 15 are noticeable with remnants of a sacrificing. These were the parts of cattle carcases laid on the bottom of the pits. Two sacrificial pavements were discovered at the centre of the excavation site. One of them was constructed using stone slabs, clay cones and fragments of large wares. The base of the second pavement had two layers. The lower layer was constructed using animal bones, while the upper one was laid with stone and clay cones. Speaking about the artefacts, the researchers note quite a high amount of the arrowheads (up to 30 specimens) found within the layers of the ash hill. Rich and numerous materials, collected on the ash hill 13 allowed to build a chronological frame within the mid. 7th – late 6th centuries BC.

Продовжено дослідження зольника № 10, розташованого в центрі Західного укріплення. На площі 111 м2 відкрито господарські ями, три будівля, виявлені різні предмети ранньоскіфського часу. В заповнені комплексів виявлені жертвоприношення тварин, людські рештки. Культурний шар, потужністю від 0,55 до 0,80 м, залягав на глибині 0,20—0,35 м. В стратиграфії зольника виділено різні шари та визначено північна межа зольника. Завершення роботи в приміщенні 3 (Південне житло). В плані воно мало чотирикутну форму, глибиною 1,8 м. В східній частині комплексу виявлена господарська яма діаметром 1,5 м та глибиною 0,9 м. В заповнені виявлено фрагменти кераміки, бронзова сережка, кісти тварин. Античний імпорт представлений уламками вінець, стінок амфор та столового посуду кінця VII — першої половини VI ст. до н.е. До цього ж часу належать і 3 будівлі (4-6), відкриті в центральній частині розкопу. В плані вони мали округлу форму, глибиною близько 1,0 м (5 и 6) и 1,9 м (4). Крім фрагментів місцевого ліпного посуду, в їх заповнені виявлені уламки античної кераміки, бронзовий и залізний наконечники стріл, фрагменти залізного браслету, бронзова сержка. 11 господарський ям розташовувалися рівномірно по площі розкопу. Всі вони мали округлу в плані форму, діаметром від 0,7 до 1,7 м и глибиною от 0,4 до 1,5 м. В двох ямах виявлені людські рештки, в двох — жертвоприношення тварин. Цікавою є знахідка глиняної фігурки коня. Серед речового матеріалу в культурному шарі зольника виявлено фрагменти кістяного псалія, виробленого в звіриному стилі, залізні ножі, голки, браслети, деталі кінської упряжі, бронзові булавки, наконечники стріл, пастове намисто. Крім багато численних уламків ліпного посуду місцевого виробництва (горщики, миски, корчаги, черпаки),виявлені уламки грецьких амфор та декілька фрагментів античних столових посудин кінця VII — третьої четверті VI ст. до н.е.

In 2012, the researchers worked at the eastern part of ash hill 10 where 263 m2 was dug out. In total, three pit-houses were explored in this area. Pit-house 4 measuring 3.65 × 4.1 m and 1.2 m deep, had an oval form. It was filled with numerous deposits of kitchen wares and also is distinguished by several skeletons of the sacrificial animals that were deposited at the different levels of this complex. Pit-house 5 measuring 5 × 4.7 m and 1.4 m deep, had an oval form. The majority of the collected artefacts consists of handmade local pottery and scattered animal bones. Pit-house 6 measuring 7.7 × 5.7 m and up to 1.75 m deep, had an oval form. An entrance was traced at the southern wall. Additional household pit 0.75 m deep was dug out in the centre of the dwelling. It was filled with a lot of daub fragments together with kitchen wares. Another interesting feature is a line of small postholes 5 cm in diameter that crossed the floor. Possibly, they remained from a light timber frame wall that divided the dwelling into two parts – for living and for husbandry utensils. The pit-house was filled with layers of ashy soil together with the debris of everyday life, mostly scattered pottery fragments. Several skeletons of the sacrificial animals were traced at the different horizons of the object. Possibly they mark certain stages of dumping the object. A cultural layer up to 1.1 m thick was deposited above the described dwellings. It contained rich and numerous materials including local and Greek wares, different tools like spindle whorls, metal adornments such as bronze pins, bracelets, earrings, etc. Objects and layers explored within ash hill 10 and beyond are lay within the wide chronological frames from the late 7th to early 5th c. BC.

In 2014, excavation site 2 was placed near the eastern entrance to the hillfort, between the rampart and the ash hills. Previously, huge storage for keeping fertilizers stayed here. Despite that, a cultural layer up to 1 m thick was detected at this place. In total, 141 m2 was dug out within the excavation trenches where the researchers explored six household pits and collected more than 10 thousand artefacts. Pit 1 measuring 1.5 in diameter and 2.1 deep. It is distinguished with pieces of carcasses discovered at the upper part of the object. Fragments of the Greek amphorae are dated by the late 6th – early 5th c. BC. Pit 2 measuring 2.4 × 1.95 m and 2.5 m deep had a posthole at the centre of it. Possibly it was a small household cellar or a storage. A skeleton of a pig that possibly was sacrificed, laid at the bottom in the corner. The most notable materials from this pit are the pieces of iron ore and amphorae fragments with traces of repairing. Pit 3 measuring 2 m in diameter and 1.9 m deep. It is distinguished by a find of a pendant made from a dog fang. Pit 4 measuring 1.6 × 1.35 m and 2.3 m deep. It was filled with layers of ash mixed with black soil. Besides the mass material, such as pottery shreds, fragments of a clay altar decorated with grooves on the outer surface, were found here. Pit 5 measuring 2.2 × 1.95 m and 2.9 m deep. It had 4 stairs dug out in the clay walls that go down the spiral to the bottom. Perhaps, it was a small household cellar or storage that after abandoning was dumped with ash and household wastes. The majority of the finds come from the cultural layer. It was a lot of fragments of pottery and even the whole broken wares. Also, a lot of bone and horn tools, such as pieces of psalia, diverse beads, pins and even a bow tip were detected here. Greek wares collected on the site originated from different Mediterranean centres such as Klazomenai, Chios, Lesbos and Thasos. Especially interesting are the fragments of black-glazed North-Ionian jar and rare South-Ionian oenochoe that dates by the late 7th c. BC. Besides that, some materials of the pre-Scythian period were found at the lowest parts of the cultural layer. Mostly, these are the pottery fragments decorated with stamped and carved geometrical ornament.

In 2015, the researchers resumed exploration of ash hill 13 on the Western Bilsk hillfort. The excavation trench measuring 141 m2 was placed on the central part of the complex where the cultural layer reached a 0.8 m thick area. In total, almost ten thousand artefacts and ecofacts were collected during the field season. Dwelling 5 was partly explored. It was an oval pit-house measuring 6.5 × 3.25 m and up to 1.45 m deep. An open fireplace was placed under the western wall at level 1.35 m. The bottom of the dwelling was filled with white ash covered with a layer of white clay. Above the fireplace, the dwelling was filled with ashy mixed soil together with numerous deposits of the artefacts. Handmade pottery, mostly pot rims decorated with punctures, constituted the majority of the finds. The researchers also draw attention to the find of the miniature ritual vessel and Klazomenai amphorae fragments dated by the late 7th – early 6th c. BC. Near the dwelling, the researchers explored an additional household pit 2 m deep. Numerous materials were discovered in the cultural layer above the dwelling. Namely, a lot of the Greek amphorae fragments and table wares with red paintings were detected here. A rare find of the black-painted oenochoe fragment with an image of a wild goat is the most notable. Crafts of the local people can be described after the finds of the pieces of iron ores and bronze ingot. Also, diverse objects of everyday use were found here: iron knife and chisel, clay spindle whorls, horn psalia, bone pins and tools for leather currying and trimming. Weapon finds are the bronze arrowheads and bronze armour scale. Also, a semi-finished bone arrowhead was found here. Several deposits of the animal skeletons were explored in the different areas. These were the parts of the carcases of a sheep, a cow, and a dog. Also, a very interesting find is the fragment of a human skull. The cultural layer above the dwelling 5 dates by the 6th c. BC.