7 Best Sights in Reykjanes Peninsula and the South Coast (with the Golden Circle), Iceland

This world-renowned therapeutic pool is now a sheltered site where man-made structures blend with natural geologic formations. A reception area includes food concessions and boutique shops where you can buy health products made from the lagoon's mineral-rich ingredients. Bathing suits are available to rent, and high-tech bracelets keep track of your locker code, any purchases, and the length of your visit. The lagoon is only 20 minutes from Keflavík Airport and 50 minutes from Reykjavík by car. Buses run from the BSÍ bus terminal in Reykjavík to the Blue Lagoon frequently. Booking in advance is essential. For a more personalized experience, you can also book a spa treatment at the lagoon's on-site Retreat Hotel, whether or not you're staying there. This is a little-known way to have your own private lagoon experience.  The Blue Lagoon has occasionally closed over the last few years due to volcanic activity in the immediate vicinity, so be sure to verify that it's open before planning a visit.

Taking a dip in a cold, refreshing lake quickly followed by a mad dash back to a hot tub or sauna is a unique healing exercise that rewards you with a rush of endorphins. If you think it's too chilly for that, just take a soothing soak in Laugarvatn Fontana's warm geothermal tubs. While you're there, don't miss their charming geothermal bakery, where you can join a guided tour twice daily (at 11:45 am and 2:30 pm) year-around, with an extra 10:15 am tour added from June to September.

Imagine yourself taking a dip in a natural hot spring surrounded by green fields and a tiny geyser, but without the crowds. It might sound too good to be true, but locals have left this lagoon largely untouched with newer facilities to enrich your experience. It's even more magical during winter when people sit in the warm water with steam rising all around them. If you're lucky, the northern lights will put on a show across the sky while you're there.

This colorful geothermal area, with raw bubbling mud pots and steam and hot little rivers emerging from the earth, is one of the gems of the Reykjanes peninsula. Located on the scenic Krýsuvík road (Route 42)—which passes volcanic sandstone cliffs, lakes with black-sand beaches, and outlandish lava formations—this stop is a must along the interesting drive. The minerals spewed from the ground at unbelievable temperatures stain the rocks in blood reds, deep blues, beige yellows, and neon greens. The nicely restored walking paths and spacious parking lot make it easily accessible for most visitors. There are also bathrooms available.

This geothermal field is named for Guðrún Önundardóttir's ghost, who sought revenge after being mistreated by a lawyer. After several deaths connected to Guðrún (also called Gunna), a sorcerer was sent to put her to rest in the hot spring. The walk over the historical bridge is well worth the wet clothes and the strong smell of sulfur.

This clinic is where Icelanders come to regain their health and peace of mind. Spa treatments like deep-heat mud baths and massages are available to both visitors and prescription-bearing patients. Before and after treatments you are welcome to use the hot tub, sauna, or swimming pool. There is also an on-site restaurant that offers healthy dishes made mostly from local ingredients.

Tucked away in a narrow valley beneath the notorious Eyjafjallajökull volcano lies one of Iceland's most scenic geothermal baths. Fed by hot springs flowing straight down the mountainside, the 24-meter (80-foot) pool, built in 1923, has a rugged charm. Though considered semi-abandoned and, therefore, free to use, there are still changing rooms next to the pool—though they are basic and often dirty. While the water tends to be more warm than hot, the scenic backdrop more than makes up for it.