Lake Bosumtwe, situated within an ancient meteorite impact crater, is ~8 Km (5 miles) across and the only natural lake in Ghana. It is situated ~30 Km south-east of Kumasi and is a popular recreational area. There are ~30 villages near this crater lake, with a combined population of ~70,000 people. The Ashanti consider Bosumtwe a sacred lake. According to traditional belief, the souls of the dead come here to bid farewell to the god Twi. Because of this, it is considered permissible to fish in the lake only from wooden planks. The impact crater is 10.5 km in diameter, slightly larger than the present lake, and is estimated to be ~1 million years old. Reference: Wikipedia