Thanks to Iceland’s abundance of geothermal heat, swimming is a national institution, and nearly every town has at least one sundlaug (heated swimming pool – often outdoors).
Most pools also offer heitir pottar (hot-pots; small heated pools for soaking, with the water around 40°C), saunas and hot tubs. The clean, chemical-free swimming pools and natural hot springs require a strict hygiene regimen, which involves a thorough shower with soap and without swimsuit before you enter the swimming area. Instructions are posted in a number of languages and not following these rules is a sure-fire way to offend the locals.
Editor's note: Please check the latest travel restrictions before planning any trip and always follow government advice.
1. Reykjarfjarðarlaug (Southwest Peninsulas, The Westfjords)
At the head of tiny Reykjarfjörður are the glorious geothermal pools of Reykjarfjarðarlaug. Up front there’s a concrete pool (90°F/32°C), but the real treat is 30 paces out back – a piping hot (113°F/45°C), natural, turf-fringed pool. And all around are soaring seabirds, mountains and fjord views. The pools are 14 miles (23km) southeast of Bíldudalur and 10 miles (17km) west of the junction with Rte 60.
2. Krossneslaug (Norðurfjörður, The Westfjords)
Krossneslaug is a geothermal (infinity) pool and hot-pot that shouldn’t be missed. Up a dirt track about 2 miles (3km) beyond Norðurfjörður, you’ll park, then walk down to where it sits at the edge of the universe on a wild black-pebble beach. It’s an incredible place to watch the midnight sun flirt with the roaring waves.
3. Sundhöll Reykjavíkur (Reykjavík)
Our top pick for a Reykjavík city-center swim. Sundhöllin reopened in 2017 after a year-long revamp that added an entire outdoor area with hot tubs, sauna and a swimming pool. The original indoor pool remains open, as well as the secret upstairs hot tub with excellent city views. The Sundhöll was built in 1937 and is far older than other Reykjavík pools.
4. Bláa Lónið/The Blue Lagoon (Reykjanes Peninsula)
In a magnificent black-lava field, the cyan Blue Lagoon spa is fed water from the futuristic Svartsengi geothermal plant; with its silver towers, roiling clouds of steam, and people daubed in white silica mud, it’s an otherworldly place. Those who say it’s too commercial and too crowded aren’t wrong, but you’ll be missing something special if you don’t go. Pre-booking is essential.
The superheated water (70% sea water, 30% fresh water, at a perfect 110°F/38°C) is rich in blue-green algae, mineral salts and fine silica mud, which condition and exfoliate the skin.
5. Krauma (Reykholt, West Iceland)
Water from neighbouring Deildartunguhver – Iceland’s largest hot spring – heats the modern outdoor bathing complex at Krauma with five multi-temperature hot-pots and two steam baths. Guests also enjoy a relaxation room and the brave can get their circulation going with a cold tub dip.
6. Gamla Laugin/Secret Lagoon (Flúðir, Southwest Iceland)
Soak in Gamla Laugin, a broad, calm geothermal pool, with mist rising and ringed by natural rocks. The walking trail along the edge of this lovely hot spring passes the local river and a series of sizzling vents and geysers. Surrounding meadows fill with wildflowers in summer. Increasingly popular, the lagoon gets packed with tour-bus crowds in mid-afternoon, so come earlier or later.
7. Lýsuhólslaug (Southern Snæfellsnes, West Iceland)
The geothermal source for Lýsuhólslaug pumps carbonated, mineral-filled waters in at a perfect 98°F to 102°F (37°C to 39°C). Don’t be alarmed that the pool is a murky green: the iron-rich water attracts some serious algae. Find it just beyond the horse ranch at Lýsuhóll.
8. Grettir’s Bath/Grettislaug (Tindastóll, North Iceland)
At the northern end of Tindastóll is a geothermal area, Reykir, that was mentioned in Grettir’s Saga. Grettir supposedly swam ashore from the island of Drangey and soothed his aching bones in an inviting spring. Today Grettislaug is a popular natural bathing hole, alongside a second hot-pot.
9. Reykjadalur/Hot River Valley (Hveragerði, Southwest Iceland)
Reykjadalur is a delightful geothermal valley near Hveragerði, where there’s a hot river you can bathe in. There are maps at the tourist information office to find the trail; from the trailhead car park it’s a 3km hike through fields of sulphur-belching plains (it takes roughly one hour one way). Stick to marked paths, lest you melt your shoes, and leave no rubbish.
10. Hveragarðurinn/Geothermal Park (Southwest Iceland, Hveragerði)
The geothermal park Hverasvæðið, in the center of Hveragerði, has mud pots and steaming pools where visitors can dip their feet (but no more). Groups can book ahead for a guided walk to learn about the area’s unique geology and greenhouse power.