10 Petrified Forest National Park Facts Worth Knowing

By Dr. Tony Pattiz Last verified June 21, 2026

Welcome to our roundup of Petrified Forest National Park facts. In this article we share 10 genuinely interesting things about a park where ancient logs have turned to stone. For more, see the full Petrified Forest National Park hub and our overview of Arizona national parks.

Petrified Forest spreads across northeastern Arizona, covering about 146,000 acres of high desert grassland, badlands, and the banded clays of the Painted Desert. It protects one of the largest and most colorful concentrations of petrified wood anywhere on Earth, alongside fossils, ancient dwellings, and a piece of old Route 66.

Petrified Forest National Park Facts

1. The Logs Are About 225 Million Years Old

The petrified wood here dates to the Late Triassic, roughly 225 million years ago, long before the first dinosaurs grew large. Back then this was a humid floodplain crossed by rivers, with tall conifers growing along the banks. The trees that fell and washed downstream are the ones you see turned to stone today.

2. The Wood Is Now Solid Quartz

These are not really wood anymore. Over millions of years, silica-rich groundwater seeped into the buried logs and replaced the organic material cell by cell with quartz. Iron, manganese, and other minerals tinted the result, which is why the petrified wood glows in reds, oranges, purples, and yellows. What looks like a fallen tree is actually a log of stone.

3. It Holds One of the Richest Triassic Fossil Records Anywhere

Beyond the wood, the park preserves an extraordinary record of Triassic life, including early crocodile relatives, giant amphibians, and some of the earliest dinosaurs. Paleontologists continue to make new discoveries here, and the park is considered one of the most important Triassic fossil sites in the world.

4. The Painted Desert Runs Through It

The northern part of the park takes in a stretch of the Painted Desert, where layers of clay and mudstone form rolling badlands banded in red, gray, lavender, and white. The colors shift with the light, and the overlooks along the park road are at their best near sunrise and sunset.

5. It Is the Only National Park With a Stretch of Historic Route 66

Petrified Forest is the only national park that contains a section of old Route 66. The Mother Road once ran right through here, and the park preserves the alignment with a rusting 1932 Studebaker parked beside a line of telephone poles marking where the highway used to run.

6. People Have Lived Here for More Than 10,000 Years

Humans have used this land since Paleo-Indian times, when the climate was wetter and grasslands drew game. Later peoples built pueblos here, and the park protects more than a thousand archaeological sites, from scattered tool fragments to standing ruins.

7. There Is a House Built From Petrified Wood

Agate House is a partly reconstructed pueblo built almost entirely from blocks of colorful petrified wood, assembled by ancestral peoples roughly 700 years ago. A short trail leads to it, and the sight of a dwelling made of solid stone logs is unlike anything at another park.

8. It Has Some of the Best Petroglyphs in the Southwest

Newspaper Rock, a large sandstone boulder covered in more than 600 petroglyphs, is one of the densest rock art panels in the region. The carvings record figures, animals, and symbols left by people who lived here centuries ago, and the park provides spotting scopes to view them up close.

9. Taking Petrified Wood Is Against the Law

Every piece of petrified wood in the park is protected, and removing even a small fragment is illegal. The rangers tell stories of visitors who mailed back stolen pieces along with notes of regret, convinced their souvenir had brought them bad luck. The safe and legal move is to buy a piece from a licensed dealer outside the park.

10. It Became a National Park in 1962

The area was first protected as a national monument in 1906, one of the earliest sites set aside under the new Antiquities Act, largely to stop the wholesale removal of petrified wood. Congress redesignated it as a national park in 1962. More recently it has also been recognized as an International Dark Sky Park for its clear, unpolluted night skies.

Petrified Forest packs a deep stretch of time into an easy drive. For more, see our overview of Arizona national parks and the full Petrified Forest National Park hub.

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