Þingvallavatn

About Þingvallavatn

Þingvallavatn is the largest natural lake in Iceland, about 84 square kilometers of water filling the rift valley in Southwest Iceland, partly inside Þingvellir National Park. It lies where the North American and Eurasian plates pull apart, and it averages 34 m deep with a maximum of 114 m.

Most of its water arrives underground, filtered through lava from the highlands, which is why the springs on the north shore are so clear. Silfra, a flooded fissure that opens into the lake inside the park, is where people snorkel and dive between the plates on guided trips. The lake drains through a single river, the Sog, and volcanic islands such as Sandey rise from the middle.

Lake Þingvallavatn is also one of Iceland's best-known fishing waters, home to brown trout, stickleback and four distinct forms of Arctic char. On the national park's shore the season runs from April 20 to September 15, from land only, since boats and float tubes are banned there. Until May 31 only fly fishing is allowed and every brown trout must be released. A day permit costs 2,500 ISK per rod at the service center at Leirar or online, and Fishing Card holders can fish the park's shore too, though the Kárastaðir land is excluded.

The lake is about 45 minutes' drive from Reykjavík and sits beside the first stop on most Golden Circle days, so you can see it year-round from the viewpoints and roads around the rift. Summer brings the long evenings that suit a walk or a cast along the north shore. In winter, check the official road-conditions map and weather warnings before you drive Route 36.