This stone circles are pretty interesting to me: https://www.google.com/maps/place/25%C2%B038'08.5%22S+30%C2%...

If you fly around this coordinates you can also find a lot of them:

  25 55′ 53.28″S, 30 16′ 13.13″E
  25 47′ 33.45″S, 30 40′ 38.76″E
  25 38′ 07.82″S, 30 21′ 18.79″E
  25 39′ 22.42″S, 30 17′ 03.25″E