Lake Thingvallavatn is the largest „natural” lake of the country with an area of 83,7 km². Its greatest depth is 114 m and it reaches 13 m below sea level. The greatest length of the lake is 14,5 km and width 9,5 km. Sog, its discharge, is a 19 km long salmon river Olfusa, which tributes to the country's largest glacial river. The average flow of the Sog river is 108 m³/sec. The lake's catchment area is 90% underground and the water from the thousands of cold springs has a constant temperature of 3-4°C the whole year round. The anglers, who use boats for their fishing, have to be careful and watch out for changes in the weather. The lake becomes a boiling pot, when the wind starts blowing.

The catch in the lake has always been a necessary part for the survival of the farming families on the lake.

Fishing hours: No restrictions
Fishing season: Fishing is only allowed from May 1st - September 15th.
Bait: Only fly, worm and lure. 
Contact: Guides and guards are stationed at the Service Centre and Vatnskot.

The distance from the capital is about 50 km. Open for fishing May 1st -15 Sept.