Pingvellir is a site of historical, cultural, and geological importance and is one of the most popular tourist destinations in Iceland.
It is the site of a rift valley that marks the crest of the Mid-Atlantic Ridge and the largest natural lake in Iceland.
Silfra, by virtue of its location in the Þingvallavatn, contains clear, cold water that attracts scuba divers drawn to its high visibility and geological importance; divers are literally swimming between continents.