Tuolumne County, California

Tuolumne County is a county in California, United States, in the central Sierra Nevada about
120 miles east of San Francisco. It had a population of 55,620 at the 2020 census, an estimated
53,160 by 2025, and covers 2,274 square miles (5,890 km2) centred near 38°01′N 119°56′W.

Sonora is the county seat and the only incorporated city; its postal code is 95370. The county
holds 1 city, 18 census-designated places and several smaller unincorporated communities, and it
runs on Pacific Time. Its FIPS code is 06109.

Towns & Villages in Tuolumne County

Tuolumne County has 19 named places on record: Sonora, the only incorporated city, and 18
census-designated places (CDPs) with no local government of their own. CDP stands for census
designated place; Unincorp. covers smaller communities the Census Bureau does not track as a
separate place.

Groveland and Pine Mountain Lake share ZIP 95321, and East Sonora and Mono Vista share Sonora’s
95370 — both pairs are separate CDPs but neither has a post office of its own. Chinese Camp
predates the Gold Rush-era mining camps around it and is now the smallest CDP in the county by
population.

ZIP Codes

• 95370 — Sonora (also covers East Sonora and Mono Vista)
• 95373 — Sonora (PO box ZIP)
• 95327 — Jamestown
• 95321 — Groveland (also covers Pine Mountain Lake)
• 95310 — Columbia
• 95383 — Twain Harte
• 95372 — Soulsbyville
• 95379 — Tuolumne City
• 95346 — Mi-Wuk Village
• 95309 — Chinese Camp
• 95375 — Strawberry (post office closed; mail now routed through Pinecrest)

Phoenix Lake, Cedar Ridge, Tuttletown, Sierra Village, Long Barn and Cold Springs have no ZIP
code of their own; mail there is delivered under the nearest incorporated place’s code.

Geography

Tuolumne County sits in the central Sierra Nevada, climbing from the rolling oak foothills of the
Mother Lode gold belt near Sonora to peaks above 13,000 feet along the Sierra crest. Of its 2,274
square miles, 2,221 are land and 54 are water. The county contains the entire northern portion of
Yosemite National Park, including Hetch Hetchy Valley, and most of the Stanislaus National Forest.
The Tuolumne River and its tributaries drain the county’s high country, feeding Hetch Hetchy
Reservoir, San Francisco’s primary water source.

Calaveras County lies to the north, Alpine County touches the county’s northeastern corner, Mono
County borders it to the east, Mariposa and Madera counties lie to the south, and Stanislaus and
Merced counties border it to the west. Calaveras
County, Alpine County, Mono County, Mariposa County, Madera County, Stanislaus County and Merced County all border Tuolumne.

Demographics

Tuolumne County had a population of 55,620 at the 2020 census, and the latest estimate puts the
county near 53,160 residents, a slight decline. Phoenix Lake and Jamestown are the two largest
unincorporated communities, while Sonora remains the only incorporated city. Median household
income runs $77,404, below California’s statewide figure of $95,521 (2023 ACS). Population
density works out to roughly 25 people per square mile of land, low for California and typical of
a mountain county with most of its territory in national forest and park land.

Economy & Local Life

Health care and social assistance employs the most workers in the county, about 3,347 people,
followed by public administration at 2,013 and retail trade at 1,979. Adventist Health Sonora, the
county’s hospital, is one of the largest single employers. Columbia College, part of the Yosemite
Community College District, sits just north of Sonora and serves roughly 4,500 students. The
Tuolumne Band of Me-Wuk Indians operates Black Oak Casino Resort near Tuolumne, one of the
county’s larger private employers, with a hotel, restaurants and an arcade and bowling alley.
Railtown 1897 State Historic Park in Jamestown runs vintage steam trains on the old Sierra Railway
and has served as a filming location for numerous Western movies and TV shows. The county’s
biggest annual event is the Mother Lode Fair, held each May at the county fairgrounds in Sonora.

History

Tuolumne County was one of California’s original 27 counties, organised in 1850 at statehood.
Its name is a corruption of a Native American word, talmalamne, reported by General Mariano
Vallejo to mean a cluster of stone wigwams. Sonora was founded during the Gold Rush by miners from
the Mexican border region Sonora and quickly became the county seat and the Mother Lode’s
wealthiest town.

In August 2013 the Rim Fire ignited in Stanislaus National Forest near the county’s Groveland
area and burned 257,314 acres, ranking as the third-largest wildfire recorded in California
history at the time. It scorched a large portion of Yosemite National Park and reshaped forest
management across the county’s eastern half for years afterward.

Getting There

No interstate highway crosses the county. California State Route 108 runs east-west through
Sonora and continues over Sonora Pass into Mono County; State Route 120 runs through Groveland
toward Yosemite’s Big Oak Flat entrance; State Route 49 runs north-south through Jamestown and
Columbia; State Route 132 serves the county’s western edge.

• Modesto — about 60 miles west
• Stockton — about 70 miles northwest
• Yosemite Valley — about 45 miles southeast of Sonora via Highway 120
• South Lake Tahoe — about 100 miles northeast

Columbia Airport, in the county’s southwest, and Pine Mountain Lake Airport, in the northeast,
are both general-aviation fields; the nearest commercial service is Modesto City-Schmidt Airport.
No Amtrak line runs through the county; Yosemite Area Regional Transportation System buses connect
Sonora to Yosemite Valley in summer.

Frequently Asked Questions

Where is Tuolumne County located?
It sits in the central Sierra Nevada, about 120 miles east of San Francisco, bordered by
Calaveras, Alpine, Mono, Mariposa, Madera, Stanislaus and Merced counties.

What is the population of Tuolumne County?
55,620 at the 2020 census, with a 2025 estimate near 53,160.

How big is Tuolumne County?
2,274 square miles (5,890 km2), of which 2,221 square miles are land.

What is the county seat of Tuolumne County?
Sonora, founded during the Gold Rush, is the county seat and the only incorporated city.

How many towns and cities are in Tuolumne County?
One incorporated city, Sonora, plus 18 census-designated places including Jamestown, Columbia,
Twain Harte and Groveland.

What ZIP codes does Tuolumne County use?
95370 and 95373 for Sonora, 95327 for Jamestown, 95321 for Groveland and Pine Mountain Lake,
95310 for Columbia, and 95383 for Twain Harte, among others.

What is Tuolumne County known for?
The northern half of Yosemite National Park, Gold Rush towns like Columbia State Historic Park
and Jamestown’s Railtown 1897, and the 2013 Rim Fire.

More counties in this state: Towns and villages in California.