California
Sugarloaf Ridge State Park
Verified by America’s State Parks Editorial Team – Updated February 2026
Sugarloaf Ridge State Park features the Robert Ferguson Observatory—largest public observatory in the western US—with a 40-inch telescope, 25+ miles of trails, and 49 campsites in Sonoma wine country!
Robert Ferguson Observatory
| Feature | Details |
|---|---|
| 🔭 Main Scope | 40-inch reflector |
| ⭐ Status | Largest public observatory in western US |
| 🌙 Programs | “What’s Up?” monthly events |
| ☀️ Solar | Daytime sun viewing too! |
Camping
| Option | Details |
|---|---|
| 🏕️ Family Sites | 49 (year-round) |
| ⛺ Glamping | 2 (book via HipCamp) |
| 🚐 RVs | Up to 31ft (no hookups) |
| 🚿 Facilities | Hot showers |
Trails
25+ miles—Bald Mountain Loop (8.2mi) to Sierra Nevada/Golden Gate views!
FAQ
Do I need reservations for stargazing?
Yes! Pre-registration required for “What’s Up?” and public events. Private rentals available.
🔭 California’s Stargazing Paradise
Reserve at ReserveCalifornia.
Last updated: February 20, 2026
