Wilbur Hot Springs

Wilbur Hot Springs is an off-grid hot springs retreat and 1,560-acre nature preserve in the hills of Colusa County, about 1.5 hours from Sacramento and 2.5 hours from the San Francisco Bay Area. The operator runs it on solar power and spring water alone, with no WiFi or cell service; an honor phone is available around the clock. The last stretch is about 3 miles on unpaved Bear Valley Road off Highway 20, then Wilbur Springs Road across the Silver Bridge to a cattle gate you open and close behind you. Gas up first: the nearest stations are about 23 miles away in Williams. The springs are natural, not a well. The U.S. Geological Survey's 1968 inventory recorded the Wilbur Springs group issuing from orifices into a concrete collection box with a plank cover, piped to the bathhouse for resort bathing, and NOAA's thermal springs survey lists Wilbur Springs at 153°F. The operator says the water emerges at about 143°F and has cooled to about 128°F when it reaches the Fluminarium, a Japanese onsen-style bathhouse where it runs through long flumes averaging 100°F, 105°F and 109°F. Staff set the temperatures by managing the flow. The flume water is untreated and constantly flowing. There is also an outdoor hot mineral flume, a dry sauna, a cold plunge made from an antique bathtub, and a spring-fed swimming pool that is cool and chlorinated in summer and geothermally heated without chlorine in winter. Confirmed reservations are required for every visit, day or overnight, and walk-ins are turned away. Day use runs 10 a.m. to 5 p.m. at one price, $68.82 on weekdays and $76.59 on weekends and holidays, including an 11% land-management fee. Overnight guests choose cabins, Solar Lodge rooms, historic hotel rooms or bunks, and six walk-in tent platforms open from April to October. Everyone shares a community kitchen. The screened bathing area is clothing-optional, device-free and alcohol-free, and clothing is required everywhere else. Only guests 13 and older are admitted, and pets are not allowed apart from service dogs.

Sources: wilburhotsprings.com (1), wilburhotsprings.com (2), wilburhotsprings.com (3), pubs.usgs.gov, doi.pangaea.de

Wilbur Hot Springs is in Wilbur Springs, California, within a quarter mile of a drivable road (sedan / 2wd). This listing is a developed resort or spa on the operator's own site. Pool or spring temperature on file: 105°F (very hot). Entry is charged in the $$$ band, camping on site is confirmed on the operator's own site and the listing records lodging on-site, reservations required and massage/spa. Clothing optional is the rule on the operator's own site.