<Li> Tamil Nadu: In Tamil Nadu more than 100 dolmens are identified in the Moral Pari near Mallachandram located 19 km (12 mi) from Krishnagiri district, Tamil Nadu . </Li> <Li> Telangana: In Telangana dolmen graves are identified near Thatikonda, Jangaon district . Also at Dharmasagar reservoir, Warangal Urban District, Telangana . </Li> <P> There are also dolmens in Andhra Pradesh, Karnataka, Kerala and Tamil Nadu in South India . </P> <P> Over 3,000 dolmens and other structures can be found in the North - Western Caucasus region in Russia, where more and more dolmens are discovered in the mountains each year . These dolmens are related to the Maykop culture . This great city of dolmens was built along the shores of the Black Sea from Maykop down to Sochi . The inhabitants were metal workers . The dolmens were vaults or safes of stone, with a narrow circular entrance that could be tapped with a round screw of stone . Supposedly the dolmens were used to hide and protect metal objects: gold, silver, bronze, jewels and some other treasure . Trade of these objects was done with Persia, Assyria, Egypt and Crete . The Dolmen City was pillaged and sacked by Scythian invaders in the early first millennium BC . The metal workers were enslaved . </P>

How was the roof of the burial chamber supported