The Golden Circle is the best known and most popular tourist sightseeing route in Iceland. It can easily be done as a day tour from Reykjavik. The three main sights are the National Park Þingvellir (Thingvellir), the hot spring area Geysir and Gullfoss waterfall.
The National Park is best known for the Alþing (Althing), the site of the national parliament of Iceland that was founded there in the year 930 and assembled there until 1800. The spectacular nature of the park invites for longer and shorter hikes and the area is of geological interest because of the tectonic plates that meet here. The continental drift between the North American and Eurasian Plates can be clearly seen.
Geysir in Haukadalur Valley, is the most famous sightseeing spot of Iceland. The Icelandic word Geysir derives from the Old Norse verb geysa (to gush). The best known geysir in the valley is named Strokkur (Icelandic for “churn”), because it is the only one that typically erupts every 6–10 minutes. Its usual height is 15–20 metres, although it can sometimes erupt up to 40 metres high. Because of this stunning spectacle, this sight is always rather busy. There is a big visitor centre with restaurant, café and souvenir shop.
Only a short drive away is Gullfoss - the Golden Waterfall. It descends in two stages 11 meters and then 21 meters down into the Gullfossgljúfur Canyon with its 70 meters high walls on each side. The river Hvitá (Icelandic for “white river”) flows through the valley.
Further south, also along the Hvitá River, lies the historical site of Skálholt. Skálholt was, through eight centuries, one of the most important places in Iceland because it was an ancient bishop seat. Today it features a large Lutheran church, Skálholt Cathedral, which was built between 1956 and 1963. Skálholt also serves as an education and information center of the Church of Iceland.
Also along the Golden Circle route is the small volcanic crater lake Kerið (Kerith). A small fee is charged if you would like to take the short walk up to the edge of the crater.
The geothermal town of Hveragerði is located at the edge of the mountains, about 45km south of Reykjavik. There is a lot of geothermal activity in the area and the lights of the greenhouses will be visible from far away. Nearby is also the geothermal power plant in Hellisheiði. The power plant has an interesting and informative exhibition about how geothermal energy is produced and used in Iceland.