Leningrad Oblast of two great lakes of the European Part of Russia, Lake Ladoga and Lake Onega. Its northeastern part, between the Gulf of Finland and Lake Ladoga, occupies the Karelian Isthmus. Some islands in the Gulf of Finland (including Kotlin, on which the city of Kronstadt has been built) and Lake Ladoga (including Konevets) also belong to the oblast. Much of the area of the oblast belongs to the drainage basin of the Neva, which is the only outflow of Lake Ladoga. Whereas the Neva, which flows to the Gulf of Finland (the city of Saint Petersburg is located in its
Lake Ladoga In his opinion, the primary name of the lake was "old source", associated to the open sea, in contrast to the name of the Neva River (flowing from Lake Ladoga) which would derive from the German expression for "the new". Through the intermediate form "*Aldaugja", cam about, referring to "Ladoga (city)". The lake has an average surface area of 17,891 km (excluding the islands). Its north-to-south length is 219 km and its average width is 83 km; the average depth is 51 m, although it reaches a maximum of 230 m in the north-western part. Basin area: 276,000 km, volume: