Grímsá is well known and considered one of Iceland’s best salmon rivers. It is near Lake Reyðar vatn, in Lundarreykjardalur. Small rivers and creeks drain into the lake, to some extent fed by spring water, which give Grímsá some spring feed character. Grímsá´s biggest tributary, Tunguá, runs into the river at pool number 600: Oddsstaðafljót. Tunguá is a decent salmon river and with Grímsá, their catchment area is about 313 km2. Salmon fishing in River Grimsá started in 1862 and there were some Englishmen involved. They used the lower part of the river until World War I and also somewhat during the inter-war years. After World War II and until 1970 landowners used their right to fish or leased it to various domestic parties. In 1971 a fishing club was established for both rivers and the system then leased out.