Trumer Seen Lakes, province of Salzburg, alt. 503 m, situated in the Flachgau region (at the border with Upper Austria); the three Trumer Seen Lakes are : Lake Obertrumer See: area 4.9 km2, 5 km long, 1.3 km wide and 35 m deep; Lake Mattsee (Lake Niedertrumer See): area 3.6 km2, 4.2 km long, 1.5 km wide and 40 m deep; Lake Grabensee: 2 km long, 0.8 km wide and 13 m deep. All three lakes have good water quality and many popular bathing beaches; summer tourism. The River Mattig flows from south to north through Lake Obertrumer See and Lake Grabensee, while Lake Mattsee and Lake Obertrumer See are linked by a canal. Small summer resorts situated on the Trumer Seen Lakes are: Obertrum am See (alt. 511 m), Seeham (alt. 506 m) and Mattsee (alt. 506 m).
Literature#E. and O. Danesch, Oesterreich - ein Land der Seen, 1979.