Stanislaus National Forest · California
Overview Dimond O is ideally located closest to Yosemite National Park's Big Oak Flat entrance and Hetch Hetchy. It's nestled near the banks of the scenic Middle Fork Toulumne River, where warm summer days can be spent wading and fly fishing in the refreshing waters. Recreation Nearby trails include the Carlon Falls Trail near the Carlon Day Use Area, and Yosemite National Park trails accessible from Hetch Hetchy.
Sites at Dimond O are reserved through Recreation.gov. Sites here can be reserved in advance through the official system, and they are claimed fast — cancellations then trickle back all season, unannounced, at any hour of the day or night.
| Total sites | 26 |
|---|---|
| Site types | Standard, Tent only |
| Location | Groveland, CA |
| Book through | Recreation.gov |
| Official listing | Recreation.gov |
Because sites are booked months ahead, a steady share of reservations get cancelled as trips fall through. Each cancellation instantly returns that site and those nights to the official calendar — first-come, first-served, no waitlist, no announcement. Refreshing the booking page yourself, every few minutes for weeks, works in theory. In practice, the people who get these sites are the ones who hear about the opening first.
ItOpened scans the Recreation.gov calendar for Dimond O around the clock. When a site matching your dates and your vehicle opens, you get a text with a direct link to it. You book it yourself, in your own account, at the normal price. We never book, hold, or resell — your fee pays for monitoring, and openings are first-come, so speed is the whole game.
| Pinecrest | Cancellation alerts available |
|---|---|
| Big Meadow (Stanislaus National Forest) | Cancellation alerts available |
| Meadowview Campground | Cancellation alerts available |
| New Spicer Meadows | Cancellation alerts available |
| Cherry Valley | Cancellation alerts available |
| (Lake Alpine) Pine Marten | Cancellation alerts available |
| (Lake Alpine) West Shore | Cancellation alerts available |
| (Lake Alpine) Silver Tip Campground | Cancellation alerts available |
| (Lake Alpine) Silver Valley Campground | Cancellation alerts available |
| (Lake Alpine) Lodgepole Campground | Cancellation alerts available |
| Union West - Union Reservoir (Stanislaus NF) | Cancellation alerts available |
| Sweetwater (Stanislaus National Forest) | Cancellation alerts available |
| Pines Stanislaus | Cancellation alerts available |
| Sandy Flat - Utica Reservoir (Stanislaus NF) | Cancellation alerts available |
| Lost Claim | Cancellation alerts available |
| (Lake Alpine) Backpackers | Cancellation alerts available |
| Waka Lu Hep Yo | Cancellation alerts available |
| Pinecrest Day Use Area | Cancellation alerts available |
| Pioneer Trail | Cancellation alerts available |
| Pines Group Stanislaus | Cancellation alerts available |
Page data refreshed 2026-10-29. Site facts come from the official directory listing for Dimond O; cancellation statistics come from our own scanning logs.