Kerið is a volcanic crater lake in the Grímsnes area of South Iceland. It is close to the three major sites that comprise Iceland’s world-famous Golden Circle sightseeing route.
The Golden Circle is Iceland’s most popular tourist route. Its three main highlights are Gullfoss, or the ‘Golden Waterfall’; the Haukadalur Geothermal Valley, with its many springs and geysers; and Þingvellir National Park, the only UNESCO World Heritage Site on Iceland’s mainland and the birthplace of the country’s parliament.
There are several tour operators who offer trips to the Golden Circle. As noted, many of those define their tours from others with extra stops, and Kerið crater is the most popular of these. It is approximately 40 minutes drive from Þingvellir and Haukadalur in different directions, providing visitors with two routes by which they can return to Reykjavík.
If travelling to Kerið crater alone, please be aware that there is a small entrance fee, of 400 ISK (about two Euros, or three US dollars). This is only to help the landowners preserve and protect the crater; after all, it is on privately owned land.
Other sites you may want to detour on when travelling the Golden Circle are the Sólheimar ecovillage, the Fontana Spa in Laugarvatn, the Secret Lagoon in Flúðir, and the Friðheimar tomato and horse farm.
Kerið is approximately three thousand years old, making it roughly half the age of most volcanic calderas found in Iceland. This is the major reason as to why Kerið’s slopes are red in colour, rather than a volcanic black; the iron deposits are, geologically speaking, fresh.
This vivid redness is part of the appeal of visiting this crater. The crimson rocks contrast dramatically with their surroundings, particularly the intense azure colour of the waters within the crater lake, and the verdant bursts of vegetation.
Kerið is approximately 55 metres (180 feet) deep, 170 metres (558 feet) wide and 270 meters (886 feet) in circumference. It is possible to take a path right to the crater’s edge, to fully encircle it, and to descend down to the pristine waters of the crater lake.
Many crater lakes can be found in nearby, a region known as Iceland's Western Volcanic Zone. The area surrounding it is of barren, stark lava fields, further illustrating the volcanism of the region.
Scientists believe that Kerið was once a cone-shaped volcano. Upon eruption, it is widely believed that the volcano depleted its magma reserve, causing the foundation to fall in upon itself and result in the formation it has today. Of course, this was two thousand years before settlement, so no one is quite certain.
At some point in the centuries following the collapse, Kerið crater filled with water. The resulting lake is between seven and fourteen metres deep, depending on the time of year and the amount of rainfall.
The reason why the lake is so vividly coloured is that of the minerals from the rocks, seeping into and dyeing the water the aquamarine colour for which it is renowned.