Devils Postpile National Monument

Devils Postpile National Monument is a U.S. national monument located near Mammoth Mountain in Eastern California. The monument protects Devils Postpile, an unusual rock formation of columnar basalt, "all closely and perfectly fitted together like a vast mosaic". The monument encompasses 798 acres (323 ha) and includes two main attractions: the Devils Postpile formation and Rainbow Falls, a waterfall on the Middle Fork of the San Joaquin River.

In addition, the John Muir Trail and Pacific Crest Trail merge into one trail as they pass through the monument. Excluding a small developed area containing the monument headquarters, visitor center and a campground, the National Monument lies within the borders of the Ansel Adams Wilderness.

Devils Postpile National Monument occupies a particular place in the imagination of American public lands. As a National Monument in California, it represents a deliberate choice — by the people who advocated for its protection, and by the National Park Service rangers who maintain it — to keep this landscape available to anyone willing to make the trip. That accessibility is the quiet miracle of the park system.

The pages linked below break the visit down into the four practical questions every traveler asks: where can I hike, where can I sleep, what else is worth seeing while I'm in the area, and what should I know before I show up. Each one is written from the perspective of someone planning their first trip — assume nothing, explain what's worth explaining, and skip the marketing language. If you've been here before, treat these guides as a refresher and a way to discover the corners you missed last time.

What this guide covers

Over the next four pages, this field guide breaks Devils Postpile National Monument into the practical questions every traveler asks: which trails are worth the effort, where to sleep both inside and outside the park boundary, what else is worth a stop in the surrounding region, and the small-but-essential tips that make the difference between a stressful first day and a smooth one. Use the navigation above to jump between sections, or read them in order — they're written to flow.

• Hikes — short loops, half-day trails, and backcountry routes
• Camping — drive-in campgrounds, RV sites, and backcountry permits
• Nearby attractions — gateway towns and adjacent public lands
• Visitor tips — timing, fees, weather, and what to skip

Logistics at a glance

Use this quick reference when you're putting together your itinerary. The figures below are the most-asked questions every visitor needs answered before arrival, summarized in one place.

Designation	National Monument
State	California
Entrance fee	Typically free or under $10 per person. Confirm at park entrance.
Visitor center hours	Most open daily 8–9am to 4:30–6pm. Reduced winter hours common.
Best months	Plan around the weather notes above.
Camping inside park	See the camping guide for campground details, fees, and reservation windows.
Nearby gateway towns	See nearby attractions for lodging and supply stops.