Hvítá is a river whose source is in the glacier lake Hvítárvatn

Hvítárvatn

Hvítárvatn is a lake in the Highlands of Iceland and the source of glacial river Hvítá. It is located 45 km northeast of Gullfoss. Its surface is about 30 km²; its greatest depth is 84 m....

 at Langjökull

Langjökull

Langjökull is the second largest ice cap in Iceland , after Vatnajökull. It is situated in the west of the Icelandic interior or Highlands of Iceland and can be seen clearly from Haukadalur....

 glacier in the highlands of Iceland

Highlands of Iceland

The Highlands of Iceland cover most of the interior of Iceland. They are situated above 400–500 metres and are mostly an uninhabitable volcanic desert, because the water precipitating as rain or snow infiltrates so quickly into the ground that it is unavailable for plant growth, which results...

 at 64°37′N 19°50′W. The river flows for 40 km (25 mi) before dropping down into a narrow gorge at the waterfall Gullfoss

Gullfoss

Gullfoss is a waterfall located in the canyon of Hvítá river in southwest Iceland.Gullfoss is one of the most popular tourist attractions in the country. The wide Hvítá rushes southward...

.

After this, the river flows between the Biskupstungur and Hrunamannahreppur

Hrunamannahreppur

Hrunamannahreppur is a municipality located in central Iceland, fully inland.As of January 2011, it had a total population of 795. The total area is 1375 km². The major settlement is Flúðir.-References:...

 districts. Here, one can find the confluence

Confluence (geography)

In geography, a confluence is the meeting of two or more bodies of water. It usually refers to the point where two streams flow together, merging into a single stream...

 of Hvítá and three other rivers: Tungufljót, Brúará

Brúará

The Brúará is a river of Iceland. It is fed by springs and discharges at the Rotarsandur Area and the Brúará Canyons.It shares a confluence with the Hvítá....

, and Stóra-Laxá. After this confluence the river contains double the amount of water compared to the amount at Gullfoss. The river then runs down through the flatlands near Grímsness and behind the mountain Ingólfsfjall. Just north of the town Selfoss it joins the Sog River

Sog River

Sog is the largest freshwater river in Iceland in terms of water volume. Average flow is 110 m³/s. It runs from Lake Þingvallavatn for 21.9km to its confluence with the river Hvítá, forming the river Ölfusá which then runs for another 25 km into the Atlantic Ocean.There are three hydroelectric...

. After that the combined river is called Ölfusá

Ölfusá

The Ölfusá is a river in Iceland. It is formed when the rivers Hvítá and Sog combine, just north of the town of Selfoss and flows for 25 km into the Atlantic ocean. It is Iceland's largest river with an average flow of 423 m³/s. Its discharge area is 5760 km². The Ölfusá has a strong salmon...

 as it flows into the Atlantic Ocean

Atlantic Ocean

The Atlantic Ocean is the second-largest of the world's oceanic divisions. With a total area of about , it covers approximately 20% of the Earth's surface and about 26% of its water surface area...

.

Because of the danger of flooding, especially in the wintertime, it has the reputation of being the most dangerous river of Iceland.

There are organised raft

Raft

A raft is any flat structure for support or transportation over water. It is the most basic of boat design, characterized by the absence of a hull...

ing excursions on parts of this river.