EXPLORATIONS ON ADA TEPE HILL (Hristo Popov – popovhristo@yahoo.co.uk, Krasimir Nikov) Mining activities were documented in the Central Sector on the top of Ada Tepe Hill, situated under the settlements of the Late Bronze and Early Iron Ages and under the sanctuary of the Hellenistic period. The radiocarbon dates showed that the end of the 15th century BC was terminus post quem for the gradual suspension of the mining activities and the use of the site for construction of buildings. The stone fortification wall, 2.60 m wide, was related to the settlement of the Late Bronze Age and protected an area of over 2000 sq. m. The radiocarbon dates showed that the settlement existed until the end of the Late Bronze Age: the middle or the second half of the 11th century BC. During the Early Iron Age the settlement reduced its size, although the occupied area partly remained the same. The Early Iron Age structures were situated mainly outside the Late Bronze Age fortification wall. The finds included Thracian ceramic vessels, stone and flint tools, moulds for producing bronze tools and jewelry, an iron bead, a bronze knife and bronze chisels. Two parallel supporting walls were documented in Sector I–7 on the northeastern slopes of Ada Tepe Hill and during the Late Bronze Age buildings were constructed in the area above them. The stratum was up to 80 cm thick. Some of the buildings were arranged in parallel rows. Mining activities were documented in Sectors G–4 and H–6 on the northern slopes of Ada Tepe Hill. The entire face of the open mine of the Late Bronze Age was discovered on the eastern slopes. The use of fire during the mining process was documented. Thracian sherds, stone tools and animal bones were found in the tailings. The tailings were up to 3 m thick in Sectors J–11, J–12 and K–11.