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 Sevan cultural monument is the Sevanavank monastery located on the peninsula, which was until the mid-20th century an island. Another prominent monastery at the western shore is Hayravank, and further south, in the village of Noratus, is a field of "khachkars", a cemetery with about 900 "khachkars" of different styles. Additional "khachkars" are found at Nerkin Getashen on the south coast. Sevan trout ("Salmo ischchan") is an endemic species of the lake, but it is endangered as some competitors were introduced into the lake, including common whitefish ("Coregonus lavaretus") from Lake Ladoga, goldfish ("Carrasius auratus"), and crayfish ("Astacus leptodactylus"). If the