The artificial Lake Ulfljotsvatn is a part of the 19 km long discharge of the largest natural lake of the country, Thingvallavatn. It has an area of 2,45 kmē. Its greatest depth is 20 m and it is situated 100 m above sea level. Roads pass the lake on both sides of the river and the fishing permits are valid within the boundaries of the farm Efri-Bru.

The lake abounds in lake char but the catch differs and the char usually does not weigh more than 1-3 pounds When the power stations on the river were constructed, the workers did not like the black flies and almost exterminated them and the char with them. The fly stock has been recovering and so has the fish.
Daily opening hours: From 07:00 to 23:00.
Fishing season: June 1st to September 30th.
Bait: Allowed bait: fly, worm and lure.

The distance from the capital is about 74 km.