The lake is of mixed glacial and tectonic origins. It is 2,120 m (6,960 ft) long and 1,380 m (4,530 ft) wide, with a maximum depth of 29.5 m (97 ft). The lake is situated in a picturesque environment, surrounded by mountains and forests. The medieval-era Bled Castle stands above the lake on the north shore. The Zaka Valley lies at the west end of the lake.
The lake surrounds Bled Island (Blejski otok). The island has several buildings, the main one being the pilgrimage church dedicated to the Assumption of Mary (Cerkev Marijinega vnebovzetja), built in its current form near the end of the 17th century, and decorated with remains of Gothicfrescos from around 1470 in the presbyterium and rich Baroque equipment. The church has a 52 m (171 ft) tower and there is a Baroque stairway from 1655 with 98 stone steps leading up to the building. The church is frequently visited and weddings are held there regularly. Traditionally it is considered good luck for the groom to carry his bride up the steps on the day of their wedding before ringing the bell and making a wish inside the church.