Hike 2 · 50-Miler Prep Series · April 4–6, 2026

Ohlone
Wilderness Trail

Fremont to Lake Del Valle — three days across the Diablo Range through Mission Peak, Sunol Regional Wilderness, and Del Valle Regional Park.

📍 CalTopo Route Map ↗
26.4
Total miles
+7,304
Gain (ft)
−6,931
Loss (ft)
3
Days
2
Nights
20
Participants
The Ohlone Wilderness Trail is one of the classic backpacking routes in the East Bay, linking ridges and valleys of the Diablo Range across Mission Peak Regional Preserve, Sunol Regional Wilderness, and Del Valle Regional Park. This trek travels west to east — starting in the hills above Fremont and crossing open ranchland, oak woodland, and rolling ridgelines before descending to Lake Del Valle.

Terrain is typical of the Diablo Range: long climbs along grassy ridges, shaded oak canyons, and wide open hillsides used for grazing livestock. Expect changing weather with warm afternoons and cooler evenings, especially along the ridges.

Day by Day

DaySegmentMilesGainLossCamp
Day 1 · Sat Apr 4 Ohlone Trailhead (Fremont) → Star's Rest Camp 10.92 mi +3,474 ft −2,272 ft Star's Rest Camp
Day 2 · Sun Apr 5 Star's Rest Camp → Maggie's Half Acre Camp 5.82 mi +2,316 ft −410 ft Maggie's Half Acre
Day 3 · Mon Apr 6 Maggie's Half Acre → Del Valle Exit (Ardilla Area) 9.69 mi +1,514 ft −4,249 ft Exit at Lake Del Valle
Total 26.43 mi +7,304 ft −6,931 ft
1
Ohlone Trailhead → Star's Rest Camp
Saturday, April 4  ·  10.92 mi  ·  381 ft → 2,103 ft  ·  +3,474 ft gain
10.92
Miles
+3,474
Gain (ft)
−2,272
Loss (ft)
381→2,103
Elev range (ft)

The trip begins at the Ohlone Wilderness Trailhead near Fremont, climbing steadily away from the city into the open hills of Mission Peak Regional Preserve. The first several miles are the most sustained climb of the entire trek — gaining elevation steadily through grasslands and scattered oak groves.

As the group climbs higher, views open dramatically across the Santa Clara Valley and San Francisco Bay, often with hawks and vultures riding thermals overhead. After cresting the high ridgeline, the trail rolls through several smaller climbs before descending into the wooded valley where Star's Rest Camp is located.

⚠ Saturday snacks and lunch are carried in individual backpacks. Bear cans are needed for overnight storage only (dinner + dessert in the SAT layer).

🏔 Night 1 Camp

Star's Rest Camp

Picnic tables Primitive sites Pit toilet 💧 Seasonal creek (filter) Shaded canyon

Tucked away in a shaded canyon with large oak trees. Quieter and more sheltered than the exposed ridges earlier in the day.

💧 Water note — Day 1 Reliable water is not guaranteed along the ridge sections. Fill all bottles at the trailhead and carry 2–3 L per person. Seasonal creek water is usually available at Star's Rest — filter or treat before drinking.
2
Star's Rest Camp → Maggie's Half Acre
Sunday, April 5  ·  5.82 mi  ·  1,584 ft → 3,590 ft  ·  +2,316 ft gain · Hardest climb per mile
5.82
Miles
+2,316
Gain (ft)
−410
Loss (ft)
1,584→3,590
Elev range (ft)

Day two is shorter in distance but involves steady climbing eastward along the Diablo Range ridges. Rolling terrain with a few steeper segments — overall pace is moderate compared to Day 1, but gain-per-mile is the highest of the trip.

This stretch passes through open ranchland. Hikers will likely encounter grazing cattle along the trail. Stay calm, walk slowly around herds, give wide berth.

Views are expansive — wide panoramas of the East Bay hills and the distant Central Valley on clear days.

⚠ Distribute all snacks before leaving camp. Double Gatorade day — hydration is critical on the highest elevation gain section.

🏔 Night 2 Camp

Maggie's Half Acre Camp

Picnic tables Primitive sites Pit toilet 💧 Seasonal water source (filter) Open meadow Excellent stargazing

One of the more popular backcountry camps on the trail. Sits in a relatively open meadow surrounded by low hills — can be breezy but offers outstanding stargazing on clear nights.

💧 Water note — Day 2 Fill all water bottles at Star's Rest before departing — dry ridgeline ahead. Seasonal creeks may be present near Maggie's Half Acre. Confirm conditions before the trip. Fill bottles before bed — dry ridgeline again on Monday morning.
3
Maggie's Half Acre → Lake Del Valle Exit
Monday, April 6  ·  9.69 mi  ·  751 ft → 3,651 ft  ·  −4,249 ft net loss · Exit day
9.69
Miles
+1,514
Gain (ft)
−4,249
Loss (ft)
751→3,651
Elev range (ft)

The final day begins with gentle ridgeline travel before the trail gradually turns downhill toward Lake Del Valle. A series of rolling hills then commits to a longer descent into the lake basin.

This stretch provides some of the best views of the trip as hikers approach the lake, with sweeping vistas of the reservoir and surrounding hills.

The trail exits near the Ardilla Group Camp area along the shore of Lake Del Valle, where the landscape transitions from backcountry wilderness to developed park facilities.

📍 Drinking water, bathrooms, and picnic areas at Lake Del Valle on exit. Celebrate with a meal in Livermore or Pleasanton!

🏁 Exit Point

Lake Del Valle  ·  Ardilla Group Camp Area

Bathrooms 💧 Drinking water (tap) Picnic areas Ranger station Parking

Del Valle Regional Park — reliable tap water, bathrooms, and parking. Shuttle car or pickup point.

Conditions & Hazards

👚

Permits required

Required for ALL campsites in the Ohlone Wilderness. Carry confirmation — rangers check.

🌿

Poison oak

Common throughout East Bay hills. "Leaves of three, let it be." Wear long sleeves on brushy sections.

🦄

Ticks

Common in grassy areas in spring. Tuck pants into socks. Full-body tick check every evening before bed.

🐄

Livestock

Active grazing on Day 2 ranchland. Stay calm, walk slowly around herds, give wide berth.

Sun exposure

Long exposed ridgelines all 3 days. Hats, sunscreen, sun shirts mandatory.

💧

Water sources

All natural sources must be filtered or treated. Seasonal only — no guarantee. Carry 2–3 L leaving trailhead.

📶

Cell coverage

Intermittent on trail. Move to higher ridgeline to improve signal. Note GPS coords at each camp.

🏭

Bear canisters

Required for all food storage overnight. Pack bear cans as soon as you arrive at camp.

Emergency Contacts

East Bay Regional Parks Dispatch  ·  24/7 primary 510-881-1121
Alameda County Sheriff SAR 510-667-7721
When calling: provide trail name, nearest camp or landmark, GPS coordinates, group size, and nature of emergency.