Lake Øyeren is the ninth largest lake by area in Norway with a surface area of 84.7 square kilometers (32.7 square miles). It is 101 meters (331 feet) above sea level and 76 meters (249 feet) deep.
The name
The name of the lake (NorseØyir) is derived from øy f 'island; flat and fertile land along a waterside'.
Nordre Øyeren nature preserve
An area that includes parts of the northern ("nordre") end of the lake is an established nature preserve, listed as a Ramsar site.