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 Ladoga The Germanic toponym (Aldeigja → Aldoga) was soon borrowed by the Slavic population and transformed by means of the Old Russian metathesis "ald- → lad-" to . The Old Norse intermediary word between Finnish and Old Russian word is fully supported by archeology, since the Scandinavians first appeared in Ladoga in the early 750s, that is, a couple of decades before the Slavs. Other theories about the origin of the name derive it from "wave" and "wavy"; or from the Russian dialectal word алодь, meaning "open lake, extensive water field". Eugene Helimski by contrast, offers an etymology rooted in German.