Some nine layers of millennia-old Hittite ruins have been discovered in central Turkey, archaeologists at the site announced Thursday.

"We have identified nine layers of construction belonging to the Hittite period," Kimiyoshi Matsumura told Anadolu Agency (AA) in Kirikkale, where the excavation site is located.

Matsumura said he and his team unearthed a city wall dating back to the 600-700 B.C., adding that the team had found a layer underneath dating back to the 14th century B.C. The excavation area covers a huge city, said Matsumura, adding that the team would continue work even if it took more than 100 years to unearth the entire area.

The Hittite Empire in the late Bronze Age was one of the civilizations that played an important role in the political and social life of its time. The Hittites left many written tablets, mostly political and commercial correspondences with Egypt and other neighboring political powers which allow archaeologists to shed light on their history and civilization. Since certain structures and architectural groups at the ancient site have been perfectly preserved, the ancient city of Hattusa, which was the capital city of the Hittites until their fall in 1178 B.C., was added to UNESCO's World Heritage list on Nov. 28, 1986.