Paris - French archaeologists said on Tuesday that they had uncovered the remains of three large towns that may have been the heart of a legendary Islamic kingdom in Ethiopia.

Ancient manuscripts have long told of the kingdom of Shoa, which between the 10th and 16th centuries straddled key trade routes between the Christian highlands and Muslim ports on the Red Sea. But Shoa's precise place on the map has never been clear.

The National Centre for Scientific Research (CNRS) said a team of archaeologists had laid bare the remains of three medieval towns, Asbari, Masal and Nora, on a high escarpment of the Rift Valley.

Shoa - also written as Shewa - was an autonomous state from about the 10th century until it was absorbed by the sultanate of Ifat at around the end of the 13th century.

The three towns "may have constituted the heart of the Shoa Muslim kingdom before it came under Ifat's political control," the researchers, led by the CNRS' Francois-Xavier Fauvelle, suggest.

The area today is covered in thick brush and scrub, but still bears the vestiges of terraced farming from hundreds of years ago, it said in a press release.

"Mosques, residential areas, walls and various buildings whose remains are several metres (yards) high" stud the sites, the CNRS said.

In Asbari, the team found the remarkably well-preserved remains of a mosque that they believe to be one of the biggest in Ethiopia, whose walls are adorned with inscriptions in Arabic. They also found a cemetery covering several hectares (acres) that contained hundreds of graves.

In Masal, they found a necropolis with a tomb emblazoned with stars and Arabic inscriptions that may have been a royal sepulchre.

Nora was clearly once a "dense urban centre," with a network of streets and the remains of roads, and whose main mosque has remains of walls up to five metres high. The archaeologists found large numbers of tools made of obsidian, a rock that is a kind of naturally occurring glass.

The discovery was made in an area about 11km long, around 45km south-east of the town of Shoa Robit, in the Ifat region, the press release said.

Further work is being planned for next year to map Nora and carry out a dig there. - Sapa-AFP