Mercey Hot Springs

What to expect

Mercey Hot Springs is a small, privately owned resort at the end of a long, quiet road through the dry hills of the Little Panoche Valley, in the far northwest corner of Fresno County. It feels remote because it is. There is no cell signal, almost no traffic noise and very little artificial light, and the resort runs on solar power off the grid.

The water is the draw. The resort says it leaves the source at about 112°F44°C, while Wikipedia lists the main spring at 119°F48°C and an artesian well at 110°F43°C. It is a salty, sodium chloride water, with total dissolved solids of about 2,300 parts per million in the resort’s own analysis, and a faint sulphur smell that most people stop noticing after a few minutes. The operator says the site has about 20 soaking tubs in total.

There are three ways to soak:

• Outdoor hot tubs behind the cabins, kept at 102-106°F39-41°C with untreated water straight from the source. These are clothing optional and for adults 18 and over.
• Private indoor tubs in the bathhouse, also clothing optional.
• A heated mineral-water swimming pool at 85-90°F29-32°C. Swimsuits are required, and the pool is chlorinated to meet Fresno County health rules.

The pool and tub areas are designated quiet zones. Talking is kept to a near whisper, there is no music and phones are frowned on. It is a place to sit, soak and watch birds and rabbits, not a party pool.

The resort and its history

The springs were used by Native Americans long before settlers arrived in the mid-1800s. Little Panoche Road began as a stagecoach route serving the New Idria quicksilver mine. A sheep rancher named John Merci acquired the land and later anglicized his name to Mercy. In 1912 he sold to Frederick Bourn, a San Francisco developer, who built a hotel, an annex and seven cabins. Bourn added the extra “e” to the name so it could be trademarked and the water bottled and sold through pharmacies.

The hotel burned in the mid-1930s. A bathhouse took its place and the old soaking tubs were moved into it. A pool and RV park came later. The current owners have been restoring the old buildings, including the former bottling plant, now known as the Chapel, and the Phoenix, a common building with a library and massage rooms.

Getting there

Mercey is about 13 miles west of I-5 on Little Panoche Road (County Road J1), at 62964 Little Panoche Rd., Firebaugh, CA 93622. Take the Little Panoche Road exit off I-5 and follow it west into the hills. The resort’s main parking area is on the north side of the creek bed, a short walk from the cabins. Overnight guests can drive to their cabin to unload, then re-park in the main lot.

Los Banos, about 35 miles away, is the nearest town with groceries and restaurants. Fresno Yosemite International Airport is roughly 1.5 hours away and San Jose International about 2 hours. There is no fuel at the resort. The nearest gas is 17 miles away at the Nees Avenue exit on I-5 (13 miles to the freeway, then 4 miles north) or 27 miles away at the Panoche Road exit (14 miles south on I-5).

When to go

Mercey is open every day of the year. Winter and spring are the most pleasant seasons. The hills turn green after the rains, migrating birds pass through, and frogs and toads come out. Campfires are allowed in designated pits from fall, after the first rain, until about Memorial Day.

Summer afternoons on the west side of the San Joaquin Valley are hot, so summer visitors tend to soak early or late. The resort is popular for meteor showers and dark-sky nights; check the moon phase before you book if stargazing is the point. The resort occasionally closes for a few weeks, most recently from July 7 to July 29, so call before planning a summer trip.

Prices and booking

• Day use: $50 per person plus fees, every day, for up to 5 consecutive hours between 12 PM and 5 PM. Day-use guests must leave by 5 PM.
• Children: Free until their 2nd birthday, then the full adult rate.
• Towels: $2 rental. Robes are not provided.
• Booking: Day use is reservation only and must be prepaid by phone at (209) 826-3388. Walk-ins are not guaranteed a place. Day-use bookings are non-refundable but can be moved to another date.
• No group discounts.
• Overnight: Cabins start at $195 plus fees per cabin (2 people maximum). Tent camping and RV sites start at $75 plus fees per person, with a 1-night minimum. Overnight stays include the waters. Check-in is 3 PM, but you can arrive from 2 PM to soak. Check-out is 11 AM, and you can keep using the facilities until 2 PM.

The resort’s online booking system was down in October 2026, so phone for anything beyond the dates already open online.

Rules and etiquette

• No glass and no alcohol in the pool, hot tub or bathhouse areas. Plastic bottles and thermoses are fine.
• No food, oils or lotions in the pool and tubs.
• No smoking or vaping of any substance anywhere on the property. There is a $200 fee for evidence of smoke indoors.
• No amplified music. Earbuds only, kept quiet.
• Quiet time is 9 PM to 8 AM.
• No pool toys except the noodles provided and children’s arm floats or life vests.
• All visitors must register at the office, and nobody may watch friends or family in the pool or tubs without a pass.

Where to stay nearby

Staying on site is the simplest option. Mercey has 9 cabins, Airstream trailers, a tiny house with its own private tub (no children), a group house called Walkabout for up to 6 people, 12 campsites and 10 RV sites. The cabins are small early 1900s buildings with a queen bed, heat and air conditioning, and shared restrooms 25 to 75 feet away. There is no restaurant, but a free community kitchen with propane grills sits next to the Phoenix, and the office sells snacks and drinks.

For motels and chain hotels, Los Banos is the closest town, about 40 minutes away. The Bureau of Land Management’s Panoche Hills land starts about half a mile from the resort and is good for longer hikes.

Safety notes

• Heat: The outdoor tubs reach 106°F41°C. Keep soaks short, drink water and get out if you feel lightheaded. Summer air temperatures add to the strain.
• Water: The spring water is drinkable but salty. The resort sells bottled water and offers filtered mineral water at a refill station by the pool house.
• No signal: Download maps and directions before you leave I-5.
• Kids: Children under 12 must have an adult with them at the pool and tubs. There is no lifeguard.