River Víðidalsá flows from the moorlands in Húnavatnssýsla down to Víðidalur and falls into the lake Hóp, then to the sea at Bjargós, west of Þingeyjarsandur. The total length from source to sea is estimated at 67 km. About 7 km from Víðidalsá estuary into Hóp, the small river Dalsá flows into it from the east. There is the well-known fishing spot Dalsárós. By Víðidalstunga the river Fitjaá falls into Víðidalsá. It is the biggest tributary with over 280 square km catchment area and is fishable up the whole Fitjárdalur. Víðidalsá itself is fishable up to Kolugil, which is about 25 km from the estuary to Hópið. The river is well-known for big salmon and the average weight is unusually high at about 4 kg. Every year salmon over 10 kg are caught. Víðidalsá is also a very good sea-char river, with a lot of fish around 3-4 lbs. and up to 6-7 lbs. caught every summer. The river is fished for two or three days at a time. The average catch in the last 10 years is 1050 salmon.