Þingvellir, anglicised as Thingvellir, is a national park in southwestern Iceland, about 40 km northeast of Iceland's capital, Reykjavík. The park is a site of historical, cultural and geological significance, and is one of the most popular tourist destinations in Iceland. The park lies in a rift valley that marks the crest of the Mid-Atlantic Ridge and the boundary between the North American tectonic plate and the Eurasian. To its south lies Þingvallavatn, the largest natural lake in Iceland.