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
Ladoga Canal Chornoe was completed and opened to traffic in 1726. This greatly accelerated work, as the completed section was used to deliver supplies to the construction site. The locks were constructed at Shlisselburg and Novaya Ladoga to maintain the depth needed for navigation. Construction of the canal was completed on October 22, 1730, and in spring 1731 the first boats were able to sail along the canal between the Volkhov River and the Neva River (Ladoga Canal proper). It turned out that the canal had a depth of less than one metre, considerably less than envisioned by Peter I. This was