Petrified Forest National Park: Hiking Among 225-Million-Year-Old Trees

Most people drive past Petrified Forest National Park. The name sounds like something from a natural history textbook, not a hiking destination. That assumption is wrong, and it costs drivers on I-40 one of the more visually strange landscapes in Arizona.

The park holds 225-million-year-old trees, mineralized to stone and scattered across high desert badlands. The Painted Desert badlands along the park’s northern border rank among the most striking terrain in Arizona. And the park draws fewer than 700,000 visitors a year, a fraction of what the Utah parks see for terrain that’s just as good.

The Trees: What Happened Here

The petrified wood comes from the Late Triassic period, 225 million years ago. A forest stood here. Trees fell, were buried rapidly by sediment, and the conditions that normally cause wood to decompose didn’t apply underground.

Silica-rich groundwater, much of it from volcanic ash in the sediment layers, seeped into the buried logs over millions of years. It replaced the wood cells gradually, preserving the cellular structure while converting the material to stone. The original log anatomy is still visible in cross-sections: growth rings, bark texture, grain patterns. But it’s quartz.

Different minerals created different colors during that process. Iron oxides produce reds, oranges, and yellows. Manganese makes purples and blacks. Pure silica is white or gray. A single large log can show five or six colors across its length.

One rule that many visitors need to hear: removing petrified wood is a federal crime, carrying fines up to $325. The park estimates it loses 12 tons of petrified wood annually to theft. Picking up even a small piece counts. Leave everything where you find it.

Human History Here Goes Back a Long Way

People have lived in this area for at least 13,000 years. The Ancestral Puebloans occupied the region from roughly 300 to 1400 CE. Puerco Pueblo, along the park’s scenic drive, is a 100-room structure where around 200 people lived. The pueblo sits near the Puerco River, which provided water in an otherwise dry environment.

The petroglyphs at Puerco Pueblo are some of the most accessible in northern Arizona. Over 650 individual images are visible on the basalt boulders around the ruins. A summer solstice solar marker is pecked into one of the rocks, positioned so that sunlight hits a spiral petroglyph at sunrise on the solstice. The alignment is precise and was clearly intentional.

The Route 66 era runs through this landscape too. The Painted Desert Inn was built in the 1920s, expanded in the 1940s, and served travelers on Route 66 before the interstate bypassed it. The Fred Harvey Company operated the inn for years. The murals inside, painted by Hopi artist Fred Kabotie in 1948, are worth a 20-minute stop.

Two Sections, One Drive

The park splits into two distinct areas connected by a 28-mile scenic road. I-40 cuts through the middle.

The Painted Desert section is in the north. This is badlands terrain in layered shades of red, orange, purple, and gray. The colors come from different mineral-rich sediment layers. The Painted Desert Inn, a 1940s Route 66 landmark, sits in this section.

The Rainbow Forest section is in the south. This is where the highest concentration of petrified wood sits, and where most of the hiking trails are. Most visitors enter from the south, hike the wood-heavy trails, then drive north through the park to the Painted Desert overlooks before exiting.

The Trails

Crystal Forest Trail

Distance: 0.75 miles. Elevation gain: minimal.

The densest concentration of large petrified logs in the park. A paved loop passing hundreds of petrified pieces, some over 6 feet in diameter. The cross-section cuts here show the most vivid mineral colors in the park, reds, purples, and yellows in the same log faces.

This is the right first stop at the south end. It’s short, it’s accessible for anyone, and it immediately shows you what petrified wood actually looks like at scale.

Giant Logs Trail

Distance: 0.4 miles. Elevation gain: flat.

Behind the Rainbow Forest Museum, this very short loop passes “Old Faithful,” a petrified log over 9 feet wide at its base. The largest individual pieces in the park are along this loop. It takes about 20 minutes and is worth combining with Crystal Forest as a pair.

Long Logs Trail with Agate House

Distance: 1.6 miles. Elevation gain: minimal.

This longer loop in the southern section passes through the Long Logs area, which holds large fallen log concentrations that genuinely look like a forest floor, except everything is stone. The trail then connects to Agate House, an 800-year-old Native American structure built entirely from petrified wood. It’s one of the most unusual construction uses of any natural material you’ll find anywhere. The structure’s walls are still partially standing.

Budget 90 minutes for this one to give the Agate House stop proper attention.

Blue Mesa Trail

Distance: 1 mile. Elevation gain: 150 feet.

The most visually distinctive terrain in the park. The trail descends into a small badlands basin of blue-gray bentonite clay hills. Petrified wood has eroded out of the hilltops and sits on the slopes below. The blue-gray color against the surrounding red and tan terrain is striking in a way that photos don’t quite capture.

The trail is paved but steep in a few sections. The descent into the basin gives you the full effect of the color contrast from above before you walk through it. Come here in the morning when the light hits the clay hills at an angle.

Painted Desert Wilderness (Off-Trail)

Distance: 2-8+ miles. Elevation gain: minimal.

This is the most interesting backcountry experience in the park for hikers who are comfortable in open desert. The wilderness area north of the main road allows off-trail travel with a free permit from the visitor center. No marked paths exist. GPS navigation is required.

The terrain is open badlands, rippled clay hills in purple and red that are unlike almost anything else in the Southwest. You won’t see petrified wood concentrations here, but the raw landscape is worth the permit process for experienced desert hikers. Start early, bring more water than you think you need, and don’t rely on phone GPS alone.

Planning Your Visit

Getting there: The park is 10 miles east of Holbrook, AZ on I-40. Flagstaff is 120 miles west, Albuquerque is 200 miles east. Fill your gas tank in Holbrook. There’s no fuel inside the park.

Entrance fee: $25 per vehicle for a 7-day pass. America the Beautiful passes are accepted.

Time needed: 3 to 4 hours covers the scenic drive with 2-3 short trails. 6 hours gets you multiple trails plus the wilderness area. The park doesn’t require more than that for a complete visit.

Scenic drive: 28 miles one-way. Pullouts at every major viewpoint and trail head. Enter from the south for the wood-heavy Rainbow Forest area first, then drive north to exit near the Painted Desert.

Painted Desert Inn: Listed on the National Register of Historic Places, restored to its 1940s Route 66 appearance. The murals inside are by Hopi artist Fred Kabotie. Give it 20 minutes.

Wildlife: Pronghorn antelope are common in the north section and are often spotted from the scenic drive. Prairie dogs appear near some roadside pullouts. Collared lizards are frequent on the trail edges in warmer months.

Best seasons: March through May, and September through November. Summer brings heat and afternoon thunderstorms. Winter is cold and can bring snow to this 5,400-foot plateau. Spring and fall are the clearest and most comfortable.

If you’re choosing one trail, pick Blue Mesa. It’s the most visually different thing in the park and nothing else in Arizona looks quite like the basin below the trailhead. Pair it with Crystal Forest for the best mix of petrified wood and landscape in a half-day visit.

For a full-day itinerary: enter from the south entrance, walk Crystal Forest and Giant Logs (45 minutes total), drive to Blue Mesa (1 hour including the trail), stop at Puerco Pueblo for the petroglyphs, then drive north through the Painted Desert overlooks and exit near I-40’s east interchange. That route covers both halves of the park in sequence without backtracking. Stop at the Painted Desert Inn on the way out.