The Golden Circle’s geothermal highlights

One of the most interesting aspects of taking a Gray Line tour of the Golden Circle will be the chance to witness geothermal activity. You’ll most certainly be aware of Geysir, as it’s one of the three main stops on such excursions. But how much do you know about some of the Golden Circle’s other geothermal highlights? Let’s take a look at what else you might see while you’re travelling around this scenic and dynamic part of Iceland.

What is geothermal activity and how do you know it is happening?

Geothermal activity is caused by a natural process. It occurs where heat from magma deep under the ground warms groundwater sources and impacts its geology. Fractures and fault lines in the rock act as conduits so that this hot water is able to make its way upwards. Where it gently rises to the surface, we see it in the form of features such as fumaroles, hot springs and mud pools.

Geysers are a more extreme outcome of geothermal activity. Rainwater and glacial meltwater filters through the rock and fills large cavities underground. As it becomes superheated, this water turns to steam. Pressure steadily builds under the earth’s surface until it can no longer be held back. This takes the form of a dramatic explosion of hot water and droplets of steam which shoots high into the air as the geyser erupts through a natural vent in the ground.    

Geysir geothermal area

The Haukadalur valley, also referred to as the Geysir Geothermal Area, is Iceland’s most famous area of geothermal activity. That’s partly because of its location, as it’s conveniently situated midway between Thingvellir National Park and Gullfoss waterfall, which makes it a logical stop for tours.

But it’s also impressive in its own right. The original geyser here is called Great Geysir, which once shot water up to 90 metres in the air every few hours. But to demonstrate the process to visitors, guides used to throw soap into the vent to precipitate a reaction. This clogged it up and as a consequence it hasn’t been a regular performer for over a century.

All is not lost, however, and that’s largely thanks to another mighty gusher called Strokkur (The Churn). This impressive geyser shoots a plume of superheated water and steam high into the air every 5 to 10 minutes, making it ideal for time-conscious travellers. The wider area is also home to a range of mud pots, hot water streams and steaming vents. The area’s protected, so it should continue to be a tourist draw for many years to come.

Laugarvatn Fontana and its geothermal bakery

One of the most delightful results of Iceland’s geothermal properties is undoubtedly its geothermal spas and lagoons. They’re found in many parts of Iceland but one of the best on the Golden Circle route is Laugarvatn Fontana. This smart geothermal spa perches on the side of Laugarvatn, one of the area’s more sizeable lakes.

Bathers can enjoy views of the countryside as they relax in the warm water, or brace themselves for an invigorating dip in the much colder water of the lake itself. But the hot water also warms the black sand that forms a small beach on the shore. This too, is worth checking out.

It provides a natural oven and is the focus of Laugarvatn Fontana’s geothermal bakery. Bread dough is placed in tins that are carefully wrapped and then buried within the hot sand. After 24 hours, the tins are dug up, giving visitors the opportunity to taste warm rye bread straight from the ground. Spread with butter and topped with smoked lake trout, it’s delicious.

Secret Lagoon

Like Laugarvatn Fontana, Secret Lagoon relies on geothermal heat for its warm water. This is the oldest pool in Iceland, known to locals as Gamla Laugin. It was dug way back in 1891 at Hverahólmi, a geothermal area near Flúðir. For a time, it was forgotten, but was later renovated to give it a new lease of life. It has never been more popular.

Secret Lagoon gets its water from three sources: Vaðmálahver, Básahver and Litli Geysir. The latter is a small but functioning geyser which bursts into action every few minutes. The sulphur-rich water is deliciously warm and no matter what time of year you do your Golden Circle tour you can expect it to be somewhere in the region of 38 to 40°C.

Reykjadalur’s hot water river

Iceland also boasts a geothermal river. You’ll find it close to Hveragerði towards the south of the Golden Circle region. First you’ll need to locate the trailhead and then hike along the valley for around 3km uphill. Most people take between 2 and 2.5 hours for the round trip. You’ll eventually reach a stretch of river where hot springs bubble up and warm the water.

The river’s temperature varies a little, so it might take a bit of experimentation to find a spot that’s just right. Broadly speaking, if you dip a toe in close to the wooden boardwalk you should find that the temperature’s lovely. This isn’t a luxury spa – there are no facilities – but if you’re looking for an authentic and quintessentially Icelandic experience then this could be it.

Friðheimar tomato farm

Unusually for Icelandic farms, Friðheimar grows tomatoes, a crop that would usually fail to thrive in the country’s cold climate. But here, geothermal energy is used to heat the greenhouses in which the tomatoes grow. Because geothermal heat is so abundant in Iceland, this form of energy is cheap, making it an economically viable business.

The farm relies on a borehole that’s just a short distance from the greenhouses. The water that they tap into has a temperature of around 95°C and is piped through the greenhouses to keep them warm. Even though some of this heat is lost through the panes of glass – sunlight’s important too – it’s still sufficient for a healthy tomato crop.

Visitors to the Golden Circle can call in to the Friðheimar tomato farm for a tasty lunch. The menu showcases many different dishes, from classics like tomato soup to more unusual items such as tomato ice cream. It’s also possible to take a tour of the farm and learn a little about the methods of production they have adopted.

Hellisheiði Geothermal Power Plant

Hellisheiði is Iceland’s largest power plant and is located within a short drive of Reykjavik. If your Golden Circle route loops down to Selfoss, you’ll easily be able to incorporate a stop here into your itinerary. It might not seem a typical holiday activity, but if you have a keen interest in science, then it’s definitely worth checking out.

The Geothermal Exhibition welcomes visitors and its exhibits explain about geothermal energy and its sustainable nature. You get to tour the power plant’s turbine halls and find out how electricity and hot water are produced to serve the capital region. Self-guided tours take about an hour and are possible all year round.

While Geysir steals the headlines, as you’ll have seen there are lots more places in the Golden Circle region that are shaped by geothermal activity. So instead of booking a standalone Golden Circle excursion with GrayLine, why not upgrade your experience and add on Secret Lagoon or Laugarvatn Fontana as well?