Spas with walk-ins welcome

Ainsworth, British Columbia

A lakeside hot springs resort in British Columbia's Kootenays with public thermal pools, a spa, restaurant and overnight rooms, closed Tuesdays.

Kuala Lumpur

An onsen-style day spa in Kampung Baru, Kuala Lumpur, with thermal pools, sauna, steam room and couples treatments.

Mývatn, Northeastern Region

A geothermal lagoon by Lake Mývatn in North Iceland, with hot tub, steam cave, swim-up bar and massages, open daily noon to 10pm.

Calistoga, California

A Calistoga hot springs spa built around mud baths, with private couples rooms and mineral pools open daily from 8am to 11pm.

Hanmer Springs, Canterbury

New Zealand's largest geothermal hot pool complex in Hanmer Springs, with pools from 28°C to 42°C, a lazy river, slides and alpine views.

Reykjavik, Capital Region

Eight oceanfront geothermal pools in Hvalfjörður, 45 minutes from Reykjavík, plus steam baths, a bistro and guest houses for rent.

Reykjavik, Capital Region

A tiny free geothermal footbath on the Seltjarnarnes coast near Reykjavik, good for warming your feet while watching the sunset or northern lights.

Monroe, Utah

Natural hot spring pools fed by mineral water in rural Monroe, Utah, open 24/7 with day-pass soaking and funky bus and cabin lodging on site.

Pagosa Springs, Colorado

Victorian-style bathhouse in downtown Pagosa Springs with mineral soaking tubs, a rooftop tub, sauna, cold plunge and on-site massage.

Saturnia, Tuscany

Walk-in thermal park in the Maremma countryside with four outdoor sulfur pools, hydromassage jets and a vascular circuit fed by a 3,000-year-old spring.

Mornington Peninsula, Victoria

Geothermal hot springs and day spa in Fingal on the Mornington Peninsula, with a family-friendly Bath House and an adults-only Spa Dreaming Centre.

Hot Springs, Arkansas

Thermal-water bathhouse on Central Ave in Hot Springs offering soaking pools, private mineral baths and eight spa treatments, minimum age 14.

Ho Chi Minh City

A Korean-style jjim jil bang in Ho Chi Minh City with six heated rooms, a Dead Sea mineral soaking pool, and massage, hair-wash and facial services.

Rotorua, Bay of Plenty

A Rotorua day spa built around Ngāti Whakaue hot-springs traditions, centered on a seven-step geothermal Restorative Journey with lakeview thermal pools, mud

Húsavík, Northeastern Region

Geothermal seawater baths built into the cliffs above Skjálfandi bay in Húsavík, with walk-in day passes and views toward the Arctic horizon.

Guanacaste, Río Negro

Riverside volcanic hot springs with ten thermal pools and mud baths near Rincón de la Vieja volcano in Guanacaste, Costa Rica.

Hot Springs, Arkansas

A day spa on Central Avenue in Hot Springs with outdoor mineral soaking tubs, cold plunge, infrared sauna, massage and an on-site café.

Baden bei Wien, Lower Austria

A thermal bath in Bad Vöslau with four mineral-water pools fed by the original Vöslauer spring, plus sauna and steam room.

Redstone Historic District, Colorado

A ranch property in Colorado's Crystal River Valley with three tiered natural hot springs pools open to day visitors and overnight guests alike.

Carson, Washington

A clothing-optional, adults-only mineral hot springs bathhouse in Carson, Washington, with a $12 day pass and a $30 bath-and-wrap treatment.

San Miguel de Allende, Guanajuato

A Saturday-only hot springs day spa near San Miguel de Allende with outdoor thermal pools and walk-in access.

Sáchica, Boyacá

Natural thermal pools and a relaxation lounge at the edge of Villa de Leyva, open daily except Wednesday with day passes for families and couples.

Ourense, Galicia

An outdoor hot-springs spa in Ourense with thermal pools, walk-in day passes, and hours that run late on weekends.

Krabi

A moderately priced onsen-style day spa in Ao Nang, Krabi, open daily from late morning into the night.