It has been identified that people started to settle here since 4,000 B.C. according to the excavations made in Tilmen Höyük located at the coast of Karasu Brook, situated 10 km away from İslahiye district. The city had its most glorious times between 18th and 15th centuries B.C., imbedded in history as the most magnificent city just after Hattusa, capital of the Hittite Kingdom
It is located on Northeast of Tilmen Höyük, 8 m high, having circular towers involving 17 stairs. The city was built by large and straight cut stones, and composed of internal and external city walls. The city walls at tons of weight and rising with huge stones, reveal the glory of the city. The walls were built with casemate technique and with massive blocks that are reclining towards each other. Protective lions exist on two corners of the gate at the main entrance of the city on east. Streets, water channels and houses of Hittite city can easily be watched at Tilmen Höyük that is the best Archeopark of Turkey with new regulations made.