The Senegambian stone circles lie in The Gambia north of Janjanbureh and in central Senegal.
With an approximate area of 30,000 km², they are sometimes divided into the Wassu and Sine-Saloum circles, but this is purely a national division. According to UNESCO, the Senegambian stone circles are "the largest concentration of stone circles seen anywhere in the world." "These sites, Wassu, and Kerbatch in Gambia, and Wanar and Sine Ngayene in Senegal, represent an extraordinary concentration of more than 1,000 stone circles and related tumuli spread over a territory of 100 km wide and 350 km in length, along the River Gambia.
Wikipedia https://en.wikipedia.org/wiki/Senegambian_stone_circles
Address Gambia
Coordinates 13°41'28.445" N -14°52'25.341" E