Overview: Japanese people have, since time immemorial, loved Mt. Fuji, Japan's highest peak. Around the mountain's base, there are five lakes of various sizes. These are the Fuji Five Lakes, which are found in Yamanashi Prefecture, on the north side of Mt. Fuji. The five lakes were formed by Mt. Fuji's repeated volcanic eruptions, when lava flows blocked rivers or split existing lakes. In times past, and still today, the lakes are an essential part of life for residents along their shores.