Lake Biel, covering 39.8 km², is one of the three major Jura lakes. It extends across the cantons of Bern and Neuchâtel. Its landscape features vineyards, orchards, and gentle hills. The lake offers numerous leisure activities, including sailing, swimming, and boat trips. The elongated St. Peter's Island is a peninsula near Erlach. You can reach it by boat, the passenger ferry, or on foot from Erlach. On it stands a medieval monastery. There are many hiking and cycling trails around the lake.