The park lies in a rift valley that marks the crest of the Mid-Atlantic Ridge and the boundary between the North American and Eurasian tectonic plates.

[4] Þingvellir National Park (þjóðgarðurinn á Þingvöllum [ˈθjouðˌkarðʏrɪn au ˈθiŋkˌvœtlʏm]) was founded in 1930, marking the 1000th anniversary of the Althing.

The park was later expanded to protect the diverse and natural phenomena in the surrounding area and was designated as a World Heritage Site in 2004.

Dingwall and Tingwall in Scotland, Thingwall in England, Tynwald on the Isle of Man, Dinklage in Germany, and Tingvoll in Norway bear names of the same root and meaning.

His land was declared public, and then obligated to be used for assembly proceedings, and the building of temporary dwellings, and the forest to be used for kindling and the grazing of horses.

[8] The longest journey a goði (chieftain) had to travel was 17 days, from the easternmost part of the country where mountains and glacial rivers proved bothersome obstacles.

Unlike the Alþingi, the Law Council was a closed body in which only certain people enjoyed full rights: chieftains who held the office of goði, their Þingmen and later also bishops.

Executive power was strengthened under this new order, while legislative and judicial authority at first remained in the hands of the Alþingi, but was gradually transferred to the Norwegian and later the Danish rulers, until in 1662 when the King of Denmark became the absolute monarch of Iceland.

Merchants, sword-sharpeners, and tanners would sell their goods and services, entertainers performed, and ale-makers brewed drinks for the assembly guests.

Þingvellir was a meeting place for everyone in Iceland, laying the foundation for the language and literature that have been a prominent part of people's lives right up to the present day.

[11][12] According to Icelandic political scientist Birgir Hermannsson, "Thingvellir can be likened to a church or building which serves as a pilgrimage destination and as a site for the nation-state’s ritual ceremonies.

[13] The continental drift between the North American and Eurasian Plates can be clearly seen in the cracks or faults which traverse the region, the largest one, Almannagjá, being a veritable canyon.

It may also qualify on geological criteria in the future, as there has been ongoing discussion of a possible "serial transboundary nomination" for the Mid-Atlantic Ridge, which would include other sites in the Atlantic such as Pico Island.

[citation needed] Because of its natural environment, Þingvellir has been a subject in the works of several Icelandic painters, including Johannes Sveinsson Kjarval and Ásgrímur Jónsson.

Þingvellir grew popular among artists not only for its natural environment but also because it was close to the capital of Iceland, Reykjavík and thus relatively inexpensive to travel there.

Scuba diving has also become popular at Silfra Lake as the continental drift between the tectonic plates made it wide enough for divers to enjoy unparalleled visibility.