Lake Peipus Lake Peipus Lake Peipus (; ; ) is the largest transboundary lake in Europe, lies on the border between Estonia and Russia. The lake is the fifth-largest in Europe after Lake Ladoga and Lake Onega (in Russia north of St. Petersburg), Lake Vänern (in Sweden), and Lake Saimaa (in Finland). Lake Peipus represents a remnant of a body of water which existed in this area during an Ice Age. It covers , and has an average depth of , the deepest point being . The lake has several islands and consists of 3 parts: The lake is used for fishing
Lake Onega Common mammals include elks, brown bears, wolves, red foxes, European hares, blue hares, red squirrels, lynxes, pine martens, European badgers, as well as American muskrats and minks which were introduced to the area in the early 20th century. About 200 bird species from 15 families have been observed in the lake basin. Lake Onega features a large variety of fish and water invertebrates, including relicts of the glacial period such as lamprey. There are about 47 fish species from 13 families; they include sturgeon, landlocked salmon, brown trout, European smelt, grayling, roaches, Crucian carp, whitefishes, char, pike, European cisco, common