Roughly triangular, the loch is about 6 km at its longest. The burgh of Kinross lies at its western end. Loch Leven Castle lies on an island a short way offshore. The castle was the prison of Mary, Queen of Scots in 1567, and it can be reached by ferry, operated from Kinross by Historic Scotland during the summer months.
Prior to the canalisation of the River Leven, and the partial draining of the Loch in the early 19th century, Loch Leven was of considerably larger area. The fall in water level exposed several small islands, and greatly increased the size of the existing ones.
St Serf's Inch is the largest of Loch Leven's seven islands and it was the home of a Culdee and then an Augustinian monastic community, St Serf's Inch Priory. There was a monastic community on the island which was old in the 12th century. The monastery produced a series of Gaelic language charters from the 11th and 12th centuries which were translated into Latin in the late 12th century.