 The biggest lakes in the area are Lake Seliger, with the town of Ostashkov located on its shore, Lake Volgo and Lake Sterzh (parts of Upper Volga Reservoir), and Lake Sig.Both Seliger (via the Selizharovka River) and Sig drain into the Volga, Verkhyaya Volga Reservoir is built in the upper course of the Volga, and the Volga flows through Lake Volgo.Minor areas in the northwest of the district belong to the basin of the Pola River in the basin of the Neva, and rivers in the northeast of the district drain to the Shlina River, also in the drainage basin of the Neva.