Tanzania is working to restore an ancient city, buried under rocks at Engaruka escarpments of Monduli District, to promote tourism in its recently launched geopark, according to an official from the Ngorongoro Conservation Area Authority (NCAA).

John Pareso, an official with the NCAA, said on Sunday that efforts to excavate, restore and protect the ruins of ancient stone structures, which are thought to be of the 800-year-old "lost city of Engaruka," have started under the recently launched Ngorongoro-Lengai Geopark.

"Remains of these stone buildings here have been scientifically proved to date back to between 500 and 800 years ago, indicating advanced civilization that may have existed in northern parts of Tanzania nearly one thousand years ago," he said.

According to Pareso, the ruins also indicate that the people of that era ran a very efficient irrigation system, whose infrastructure can still be seen within the ruins.

Archaeological experts are still trying to find out what caused the ancient Engaruka settlement to be abandoned or destroyed.

Tanzania, with the support from the United Nations Organization for Education, Science and Culture (UNESCO) and through the Ngorongoro-Lengai geopark, is working to restore the ruins, which of late have started to attract researchers, scholars and tourists alike.

The newly endorsed UNESCO geopark covers three northern districts of Arusha Region, Monduli, Longido, and Ngorongoro.