Lake Thverarvatn has an area of 0,64 kmē and is situated 519 m above sea level. River Thvera connects it with lake Anavatn and continues as its discharge until it changes names and becomes river Garda, which tributes to the glacial river Jokulsa a Bru, just west of the farmstead Bru from where the lake is accessible by 4wd vehicles. The lake is netted and the catch consists of lake char.

The distance from the capital is about 582 km by the Whale Bay tunnel and 93 km from Egilsstadir.