Tumuluses, supposed to be graveyards of kings, are located in Kabaoğlu Uctepeler village 3 km away from Izmit. Three of the tumulus's are inside the village and the remaining four are out of the village.
Two of the tumulus's were located and opened by Izmit Museum Directorate. It turned out that the first tomb, called Aytepe tumulus, is a tumulus belonging to the late Hellenistic-early Roman era. The second tümülüs was opened at the entrance of the village. As a result of the archeological excavations made in the big tumulus, belonging to the Roman era as well, it was exposed to robberies in its era and no remains of the tomb could be detected.