Hattusa, also Hattuşa, Ḫattuša, Hattusas, or Hattusha, was the capital of the Hittite Empire in the late Bronze Age during two distinct periods. Its ruins lie near modern Boğazkale, Turkey (originally Boğazköy) within the great loop of the Kızılırmak River (Hittite: Marashantiya; Greek: Halys).
French archeologist Charles Texier brought attention to the ruins after his visit in 1834. Over the following century, sporadic exploration occurred, involving different archaeologists. The German Oriental Society and the German Archaeological Institute began systematic excavations in the early 20th century, which continue to this day. Hattusa was added to the UNESCO World Heritage Site list in 1986.