Lake Vistytis (sometimes Lake of Vistytis, russian Vishtynetskoye ozero Виштынецкое озеро, informal sometimes European Baikal) is a lake on the border between Lithuania (Marijampole district) and Russia (Kaliningrad oblast). It is named after the small lithuanian town of Vistytis on its northern shore. Lake Vistytis covers an area of 335 sq.km.. It is situated within a picturesque landscape of forests and hills.