It’s Titicaca and it’s a lake that’s part of both Bolivia and Peru.
Isla del Sol, Bolivia
We visited a couple of islands in the lake while crossing Bolivia to reach Cuzco in Peru. A long and super touristic trip which I don’t know if we would recommend, but here’s a few pics.
The floating islands in Peru are more photogenic, they are however super touristic, and only a 30min is enough to go around.