Stone Circles of Senegambia

The Senegambian stone circles are the densest concentration of megaliths anywhere in the world, more than a thousand monuments strung along three hundred and fifty kilometres of the Gambia river valley. Sine Ngayène in Senegal is the largest single site with fifty-two circles, one of them concentric, and Wanar holds twenty-one more including a double ring. The pillars were quarried from laterite, dressed into cylinders and set upright around burial mounds between the third century BC and the sixteenth century AD. Who raised them is not known. The four groups carry UNESCO World Heritage status together with two sites in the Gambia.