Höhepunkte: 
The Blue Lagoon is a geothermal spa found on the Reykjanes Peninsula in southwest Iceland. It is the most popular attraction in Iceland drawing people from all across the world.
The Lagoon is just a fifteen-minute drive from Keflavík International Airport, or a thirty-minute drive from Reykjavík, located between the two. It is thus often visited straight after arrival to the country or right before departure.
There are few better ways to recharge after a long-flight or action-packed holiday.
History

The Blue Lagoon started as a pool of wastewater from the Svartsengi geothermal plant in 1976. The first person to bathe there was Valur Margeirsson in 1981. He was met with some resistance prior to taking the first dip as people thought he was mad for wanting to bath in a "blue mud pool". He and others soon began to notice the unusual but remarkable healing qualities of the azure waters.
Those with conditions such as psoriasis found the waters immediately soothing for their condition. News quickly spread, and by 1987, the first swimming facilities were officially opened.
Since then, the establishment has only grown, from an open pool with no surrounding buildings to a luxurious spa, research centre and hotel.
Today
The Blue Lagoon is considered to have such notable regenerative qualities because the water is rich in silica and sulphur. A research and development facility on site finds cures and remedies for skin ailments, and silica mud is available for free on the sides of the pool for guests to enjoy a facemask.
The temperature in the bathing and swimming area is very comfortable, averaging 37–39° C (98–102° F). The Blue Lagoon also boasts the LAVA Restaurant, the Blue Café and the Lagoon Spa: you can thus enjoy cocktails, health products, delicious meals and treatments such as massages without leaving the premises. Saunas, steam rooms and a small waterfall are also on site.

For all of these reasons and more, the Blue Lagoon is considered to be one of the most enjoyable and romantic spots in the country. It is surrounded by a plethora of fantastic volcanic landscapes, and the water itself is opaque and vividly blue. Rising pillars of steam only add to the spa’s fantastic ambience.
Things to Note
The Blue Lagoon Spa is open throughout the year, and popular in every season. Due to the fact it has a maximum capacity for the comfort of its guests, it is essential that you book several months in advance to ensure your space. The vast majority of the time, you will be turned away at the door without a reservation.
More reserved guests might want to be aware that it is a requirement to shower naked in public before entering the lagoon, to ensure that the highest hygiene standards are maintained. Though uncomfortable for some, nudity has little taboo in Icelandic culture, so worry not; no-one’s looking.
Those who are travelling on a budget will note that the Blue Lagoon is quite pricey. There are other smaller spas and pools that can be entered for less, such as the Fontana Spa, Secret Lagoon, Mývatn Nature Baths and Krauma Spa. Of course, natural hot pools are free to enter.
For more information, you can read articles on the best pools in the country and the best natural hot springs.
Blaue Lagune, 
Geysir is a famous hot spring in the geothermal area of Haukadalur Valley, found in south-west Iceland.
Making up just one of the attractions along the world-renowned Golden Circle sightseeing route, alongside Þingvellir National Park and the mighty Gullfoss waterfall, Geysir is most well-known for having lent its name to geysers all around the world.
Geography
Though Geysir itself is rarely active these days, Haukadalur Valley boasts a plethora of hot springs and geysers, including the powerful Strokkur, Smiður and Litli-Strokkur.
Strokkur is, arguably, the country’s most famous hot spring, shooting vast jets of boiling water from 20 metres (65 feet) up to 40 metres (130 feet) high. Don’t worry about missing this incredible spectacle of nature, as Strokkur erupts every five to ten minutes; just make sure to have your camera ready.

Geysir is much larger, but years can go by between eruptions here; it is currently in an inactive phase. When it does erupt, the water can shoot up in the air as high as 70 metres (230 feet).
Just a few minutes walk north of Geysir are a wealth of fumaroles emanating steam and gas into the cool Icelandic air. Aside from watching the hypnotic pillars of steam, you will also be able to observe the yellow sulphuric stains along the fumaroles themselves, a result of the earth’s minerals crystallising around the rock bed.
At the southern part of the valley, Þykkuhverir, you’ll find various bubbling mud pots. These spooky brown cauldrons are actually fumaroles that boil up through the loose ground; after a dry spell, these mud pools are likely to transform into a hardened fumarole.
Nearby Attractions
About two kilometres (one mile) from Geysir is a preserved natural pool called Kúalaug. It has room for three to five people at a time, but care should be taken, as the area around the pool is very delicate. The temperature is 39-43°C (102-109°F), depending on where you are positioned in the pool.
The water is slightly muddy, as the pool is built on soil, and the bottom is slippery due to algae, so caution is advised when relaxing here.
Haukadalur has also seen a rise in reforestation in recent times thanks to continued experiments and research in the area. Today, Haukadalsskógur is one of the largest forests in south Iceland, boasting accessible walking paths (also for wheelchair users), fascinating vegetation and The Tree Museum, built in the memory of forester Gunnar Freysteinsson.
History
Haukadalur has been inhabited and used as a church site since the Age of Settlement. Given its historic value, it should be noted that scholar, Ari “The Wise“ Þorgilsson, grew up here; it was also where the first pastoral school in Iceland was built.
The current wooden church was last rebuilt in 1938 but its architectural style dates back to 1842, making it well worth a visit to see how Iceland looked before industrialisation.
For accommodation, Hotel Gullfoss is approximately 7 kilometre from the Geysir area, and closer still is Hotel Geysir on the other side of the road from the attraction, where you will also find a restaurant, café and a souvenir shop.
Geysir, 
Gullfoss (translated to ‘Golden Falls’) is one of Iceland’s most iconic and beloved waterfalls, found in the Hvítá river canyon in south-west Iceland.
The water in Hvítá river travels from the glacier Langjökull, before cascading 32 meters (105 feet) down Gullfoss’ two stages in a dramatic display of nature’s raw power. This incredible site is seen by most visitors, as it is on the Golden Circle sightseeing route.
Because of the waterfall’s two stages, Gullfoss should actually be thought of as two separate features. The first, shorter cascade is 11 metres (36 feet), whilst the second drop is 21 metres (69 feet). The canyon walls on both sides of the waterfall reach heights of up to 70 metres (230 feet), descending into the great Gullfossgjúfur canyon. Geologists believe that this canyon was formed by glacial outbursts at the beginning of the last age.
In the summer, approximately 140 cubic metres (459 cubic feet) of water surges down the waterfall every second, whilst in winter that number drops to around 109 cubic metres (358 cubic feet). With such energy, visitors should not be surprised to find themselves drenched by the waterfall’s mighty spray.
As mentioned, Gullfoss makes up a part of the highly popular Golden Circle sightseeing route, alongside Geysir geothermal area and Þingvellir National Park. Many Golden Circle tours include additional activities that can be taken from Gullfoss, such as ascending the mighty nearby glacier Langjökull and entering its ice tunnels, or snowmobiling along its gleaming surface.
History

In the early days of the last century, Gullfoss was at the centre of much controversy regarding foreign investors and their desire to profit off Iceland’s nature. In the year 1907, an English businessman, Howell, sought to utilise the waterfall’s energy and harboured ambitions to use its energy to fuel a hydroelectric plant.
At the time, Gullfoss was owned by a farmer named Tómas Tómasson. Tómas declined Howell’s offer to purchase the land, stating famously “I will not sell my friend!” He would, however, go on to lease Howell the land without the knowledge of a loophole that would allow him to proceed with his plans.
It was Tómas’ daughter, Sigríður Tómasdóttir, who would lead the charge to stop Howell’s ambitions. Having grown up on her father’s sheep farm where she helped pave the first road to Gullfoss, she sought to get the contract nullified, hurriedly saving her own money to hire a lawyer.
The ensuing legal battle was an uphill struggle; the case continued for years, forcing Sigríður to travel many times by foot to Reykjavík, a distance of over 100 kilometres (62 miles). Circumstances became so difficult that Sigríður threatened to throw herself into the waterfall if any construction began.
Her tenacity, however, resulted in success. In 1929, Howell’s withdrew from the lease, unable to keep up with the costs and difficulties of his plan. The waterfall fell back into the hands of the Icelandic people.
Today, Sigríður is recognised for her perseverance in protecting Gullfoss and is often hailed as Iceland’s first environmentalist. As such, she is one of the most famous figures in Iceland’s history. Her contribution is forever marked in stone; a plaque detailing her plight sits at the top of Gullfoss.
Interestingly, the lawyer who assisted Sigríður, Sveinn Björnsson, went on to go down in history too; he became the first president of Iceland in 1944.
Restaurant / Cafe
Besides Gullfoss, visitors can enjoy the views from Gullfoss Cafe, a locally run delicatessen that serves a wide variety of refreshments and meals. The menu has options to tantalise everyone’s taste buds: hot soups, sandwiches, salads and cakes. There is also a shop on site where visitors’ can browse and purchase traditional Icelandic souvenirs.
Gullfoss, 
Þingvellir National Park is the only UNESCO World Heritage site on the Icelandic mainland and one of the three stops on the world famous Golden Circle sightseeing route, alongside the Haukadalur Geothermal Valley (Geysir) and Gullfoss Waterfall. Just to the south of the park is Þingvallavatn, Iceland’s largest natural lake.
Geography
The first thing that visitors to the National Park notice is its sheer aesthetic beauty; dried magma fields, covered in Icelandic moss, sit carved by glacial springs and surrounded by a bowl of ancient mountain peaks.
Two of the greatest attractions in the park are the exposed North American and Eurasian tectonic plates; it is one of the only regions in the world where you can see geology such as this on land.
Visitors are encouraged to walk along the North American tectonic plate, where they can read more about the area’s fascinating formation and history, before descending into the valley below.
History

Þingvellir can be anglicised to ‘Fields of Parliament’, a nod to the area’s fascinating history and relevance to Icelandic culture. It is here, after all, that the world’s first democratically elected parliament that remains functioning, Alþingi, was formed in 930 AD.
It may seem unlikely that Vikings would want to be under such an uncombative government, but the thirty or so clans that lived in Iceland at the time sought to prosper in their harsh new environment.
The first gathering was such a success that the meetings became annual, and it became a place where disputes were settled, criminals were tried, and laws to the benefit of all were laid down.
This saw the birth of the Icelandic Commonwealth, a time of independence and freedom for the Icelandic people before they became constituents of the Norwegian monarchy. Sessions would continue to be held at Þingvellir until 1798.
Though the parliament was removed by the Danish at this time, it returned 1845 to Reykjavík.
Another major reason as to why Þingvellir is considered so important to Icelanders is the fact that this is where the decision was made to abandon the belief of Paganism and the Norse Gods; the people adopted Christianity in 1000 AD under threat of invasion from Norway.
This turning point in history was left to the pagan lawspeaker, Þorgeir Þorkelsson, who rested on the choice for one day and one night before reappearing to share his decision.
To symbolise the country’s change, he threw idols of his old deities into the northern waterfall Goðafoss, the name of which translates to ‘Waterfall of the Gods’.
Silfra Fissure
Þingvellir is one of the most widely visited attractions in Iceland, in large part due to the fact that it is home to the glacial spring, Silfra fissure, one of the top ten sites in the world for snorkellers and scuba divers.
Silfra (meaning ‘Silver’) is a submerged ravine within the park, boasting visibility of up to 100 metres (328 feet) and a temperature just above freezing. Participants in these tours will be attired at the Silfra carpark in neoprene hoodies and gloves, as well as an undersuit and drysuit for thermal protection.
Þingvellir, 
Strokkur is Iceland’s most visited active geyser. One of the three major attractions on the world-famous Golden Circle sightseeing route, it is usually visited alongside Gullfoss Waterfall and Þingvellir National Park.
Strokkur is found in the Geysir Geothermal Area, titled after the Great Geysir, which lent its name to all others across the world. It is the greatest active geyser on site; Geysir itself is in a period of inactivity. Strokkur erupts more regularly than Geysir ever did, blasting water to heights of around fifteen to twenty metres every five to ten minutes, although it is known to reach up to forty metres.
Strokkur and Haukadalur Valley

Strokkur is the primary feature of the Haukadalur valley and the main reason why it is one of the most visited sites in the country. While Geysir will very occasionally still erupt to enormous heights, it is nowhere near reliable enough to justify the area’s popularity.
Haukadalur valley, however, has many other features that make it worth a visit. The natural beauty of the area is shaped by the forces of the earth; fumaroles, hot-springs, mud-pits and other little geysers are littered around, and the ground itself is dyed vividly by elements such as sulfur (yellow), copper (green) and iron (red).
Opposite the main geothermal area in Haukadalur Valley is a restaurant, cafe, hotel and luxury gift shop.
Science behind Strokkur

Active geysers like Strokkur are rare around the world, due to the fact that many conditions must be met for them to form. They are thus only found in certain parts of highly geothermal areas.
The first condition that is necessary is an intense heat source; magma must be close enough to the surface of the earth for the rocks to be hot enough to boil water. Considering that Iceland is located on top of the rift valley between the North American and Eurasian tectonic plates, this condition is met throughout most of the county.
Secondly, you will need a source of flowing underground water. In the case of Strokkur, this comes from the second largest glacier in the country, Langjökull. Meltwater from the glacier sinks into the surrounding porous lava rock, and travels underground in all directions.
Evidence of this flowing water can be found in Þingvellir National Park, where there are many freshwater springs flowing straight from the earth.
Finally, you need a complex plumbing system that allows a geyser to erupt, rather than just steam from the ground like a fumarole. Above the intense heat source, there must be space for the flowing water to gather like a reservoir. From this basin, there must be a vent to the surface. This vent must be lined with silica so that the boiling, rising water cannot escape before the eruption.
Environmental Issues with Strokkur
One of the main reasons that Geysir entered a period of inactivity was due to the fact soap used to be pumped into the vents to make the eruptions more dramatic; it damaged the structure of the vent and prevented water building up. Strokkur, therefore, is guarded against all interference, with chains keeping visitors a good distance away.
Unfortunately, however, there have been incidents where people have meddled with its natural state. For example, an artist called Marco Evaristti once poured food colouring into it to make the eruption pink. He defended himself by claiming that nature was open to artists to utiltise and the fact the colouring was all-natural, but he became a pariah amongst many Icelanders, and was arrested and fined (though never paid it).
Strokkur, 
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 and thus makes for the perfect detour for those on visiting these landmarks.
Kerid and the Golden Circle
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. 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.
Geology of Kerid
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.
Kerið