Four Seasons Firenze Spa
Hotel SpaTuscany
Hotel spa inside Florence's Four Seasons, with a walled garden pool, whirlpool, sauna, steam room and couples suite, open to day-pass guests.
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Spas with thermal pool
13 spas match
Hashani Spa
Hotel SpaTucson, Arizona
A resort spa in Tucson's Starr Pass area with a saline lap pool, sauna and fitness center, plus signature treatments from $159 for hotel guests.
$$La Vidorra Spa at The Scott
Hotel SpaScottsdale, Arizona
Adults-only hotel spa at The Scott in Scottsdale with six treatment rooms, sauna, steam and pools, plus day passes for non-guests.
$$$Riviera Maya, Quintana Roo
Adults-only spa inside the all-inclusive Ocean Riviera Paradise resort in Playa del Carmen, with sauna, Turkish bath and four treatment options via day pass.
$$$$Scottsdale, Arizona
Hotel spa at the Inn at Eagle Mountain in Fountain Hills with sauna, steam room, pools and a $69 60-minute massage as its signature treatment.
$SpaWell at El Conquistador Tucson
Hotel SpaTucson, Arizona
Adults-only hotel spa at El Conquistador Tucson with a salt therapy lounge, heated outdoor pool and mountain views, day passes available to hotel guests.
$$The Spa at Napa River Inn
Hotel SpaNapa Valley, California
Adults-only hotel spa in downtown Napa with thermal circuits, sauna, steam and cold plunge, plus massages, facials and medical aesthetics.
$$$AWAY Spa at W Scottsdale
Hotel SpaScottsdale, Arizona
Adults-only hotel spa at W Scottsdale with thermal circuits, sauna, steam, cold plunge and a robotic Aescape massage option.
$$$JW Marriott Marquis Miami
Hotel SpaMiami, Florida
A hotel spa in downtown Miami with a day pass covering sauna, steam, cold plunge and thermal pools, plus 13 treatments on the menu.
$$San Juan
Adults-only hotel spa inside La Concha Resort in Condado, San Juan, offering couples massages and a small treatment menu for guests 18 and up.
$$$Miami Marriott Biscayne Bay
Hotel SpaMiami, Florida
Hotel spa deck in downtown Miami with sauna, steam room, cold plunge and thermal pools overlooking Biscayne Bay, day passes from $50.
$The Westin Phoenix Downtown
Hotel SpaPhoenix, Arizona
Adults-only hotel wellness setup in downtown Phoenix with a heated pool, sauna and steam room, day passes available for $50.
$Farmhouse Inn
Hotel SpaCalistoga, California
A 25-room Sonoma hotel in Forestville with a spa barn offering sauna, steam and pools, mainly for overnight guests.
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