Kerið crater

About Kerið

Kerið stands out from Iceland's other craters for its colour: the walls are a deep red from oxidised volcanic rock, in contrast to the black basalt seen almost everywhere else nearby, and the lake at the bottom often has a striking blue-green tint depending on light and season. It is thought to have formed when a magma chamber emptied and the ground above collapsed, rather than from a violent explosive eruption.

Unlike Gullfoss and Geysir, Kerið is privately owned, which is why there is a small entrance fee rather than free access. A path circles the rim with views down into the crater, and a steeper path leads down to the water's edge on one side. The whole site can be covered on foot in well under an hour, making it an easy stop between the Golden Circle's bigger attractions.

The lake is between about 6 and 14 metres deep. It has no stream running in or out; it sits at the level of the groundwater, so it rises and falls a little with the seasons. Minerals washed out of the surrounding rock give the water its aquamarine colour, which looks strongest on a bright day against the red slopes and green moss. You can do both walks here: around the rim, which takes 15 to 20 minutes, and down the stairway to the shore, which has 139 steps.

Quick facts

The geology of Kerið crater

Kerið is the northernmost of four craters along an 800-metre fissure called Tjarnarhólar, part of Iceland's Western Volcanic Zone, which runs from the Reykjanes peninsula up towards Langjökull. Scientists believe Kerið was once a cone-shaped volcano. The usual explanation is that the eruption emptied the shallow magma chamber underneath, and the cone then collapsed into the empty space, leaving a bowl rather than a peak. Other sources describe it as an explosion crater, so the question is not fully settled.

The red colour comes from iron in the rock, which has oxidised, and it is why Kerið looks so different from the black lava found almost everywhere else nearby. Older guides give the crater's age as about 3,000 years, half that of its neighbours, and use that to explain the fresh colour. More recent estimates, including the one given by the site’s owners at kerid.is, put it at about 6,500 years.

The lake formed later. Once the crater floor had settled below the water table, groundwater filled the bottom, and it has stayed there since.

How to get to Kerið

Walking the rim and down to the blue lake

Kerið is small enough to see properly in half an hour, and both paths start at the entrance.

Stay on the paths. The red scoria on the slopes is loose and erodes quickly when people walk on it.

Best time to visit Kerið

Safety and practical tips

• Wear shoes with grip if you plan to walk down to the water, as the path can be loose or icy.
• Stay on marked paths. The crater's slopes are used for weddings and events on occasion, and access can be restricted at those times.
• Combine Kerið with Faxi waterfall or Fridheimar for a fuller Golden Circle day beyond the three main stops.
• Bring small cash or a card for the entry fee, paid at the site.

Facilities and accessibility

There are toilets and a small car park at the site. No café or shop; the nearest services are in Selfoss or around Geysir.

On the map

Nearby places worth a stop

SelfossNearest town, about 15 km south

SeyðishólarGroup of red scoria craters a few minutes north

GeysirGeothermal area with Strokkur geyserGullfossIceland's best-known waterfallFaxiA quieter waterfall nearbyÞingvellir National ParkTectonic plates and Viking-age historyFriðheimarGreenhouse tomato farm with lunchReykjadalurHike to a warm river above Hveragerði

Where to stay near Kerið

Selfoss and the villages around Geysir and Laugarvatn have hotels and guesthouses within easy reach of Kerið for those spending a night on the Golden Circle route.

A hotel we know and book close by: Úlfljótsskáli Luxury Lodge. See all places to stay.

Kerið FAQ