# Petrified Forest National Park — logs of quartz that look sawn, a house built of them, and a stretch of Route 66 Canonical: https://sockmonkey.com/places/petrified-forest-national-park (this is a plain-text copy of that page) Source: https://sockmonkey.com/places/petrified-forest-national-park Publisher: SockMonkey.com (https://sockmonkey.com) Part of: The Field Guide - https://sockmonkey.com/places/ Cite as: SockMonkey.com - sockmonkey.com Last reviewed: 31 October 2026 Part of The US National Parks - **Where:** North-eastern Arizona, on I-40, east of Holbrook (NPS) - **Coordinates:** 34.815° N, 109.866° W, Rainbow Forest Museum (NPS) - **Area:** Over 200,000 acres, (NPS) - **The wood:** More than 200 million years old;, almost solid quartz (NPS) - **Protected:** National monument 1906, national park 1962 (NPS) - **Best visited:** All year, except Thanksgiving, and Christmas Day (NPS) - **Advisory:** United States, (no State Department level) ## The short answer Petrified Forest National Park lies in north-eastern Arizona, on Interstate 40 east of the town of Holbrook. A 28-mile park road runs through it from the Painted Desert at the north end, by the interstate, to the Rainbow Forest at the south end, by Highway 180. The National Park Service describes a landscape of colourful badlands and grasslands with one of the world’s largest and most vivid collections of petrified wood, spanning more than 200 million years of geological history, along with ancestral Puebloan sites, habitat for desert animals and a sweeping stretch of historic Route 66. The park is over 200,000 acres; a 2004 act authorised it to grow to 218,533 acres as neighbouring private land becomes available. President Theodore Roosevelt proclaimed Petrified Forest National Monument on 8 December 1906, citing “the mineralized remains of Mesozoic forests” as of the greatest scientific interest and value; the Park Service says it was in the second group of monuments created under the Antiquities Act, with Montezuma Castle and El Morro, after Devils Tower. Congress redesignated it a national park in 1962. ## Why it's worth knowing Who cut the wood? The petrified wood here is almost solid quartz, the Park Service says, each piece like a giant crystal, its rainbow of colours coming from impurities such as iron, carbon and manganese. More than 200 million years ago the logs washed into an ancient river system and were buried so quickly and deeply that oxygen was cut off and decay slowed; over hundreds and thousands of years, minerals including silica dissolved from volcanic ash soaked into the wood and crystallised in its cells as the wood broke down. Where the logs had cracked, crystals of clear quartz, amethyst, citrine and smoky quartz grew. Then, from about 60 million years ago, the rising Colorado Plateau broke the buried trunks like glass rods. Most of the petrified trees have been given the scientific name Araucarioxylon arizonicum. The trees did not fall at once, the Park Service adds: they died over some 20 million years, from beetles, fungus, lightning, floods and wind. The ash that paints the hills. The same volcanoes, far to the west in what are now California, southern Nevada and western Arizona, sent ash on the wind into the sediments of the Late Triassic, the Park Service says. The ash weathered into bentonite clay, which swells up to eight times its size when wet and shrinks and cracks as it dries, so plants find little hold and summer storms carve the bare, banded badlands of the Painted Desert. The Triassic layers also hold fossils of some of the earliest dinosaurs, among them Coelophysis and Chindesaurus. A road and a house. The Park Service says Petrified Forest is the only park in the national park system with a section of historic Route 66, the road from Chicago to Los Angeles established in 1926; weathered telephone poles still mark its old roadbed, and a 1932 Studebaker sits where it crossed the park. The Painted Desert Inn, a roadside inn of 1924 rebuilt by the Civilian Conservation Corps in 1937 to 1940 in the Pueblo Revival style, became a National Historic Landmark in 1987 and keeps murals by the Hopi artist Fred Kabotie. ## The field notes ### The stone-tree house Herbert Lore registered the Painted Desert Inn as his business in 1924, and it was soon nicknamed the “Stone Tree House” for the petrified wood in its walls, the Park Service says. The monument bought it on 29 February 1936. It was built on a vein of bentonite clay, which swells and shrinks with the weather, and Lore’s long, muddy masonry joints did not help; it cracked, closed for structural problems in April 1963, was argued over for 24 years between demolition and restoration, and reopened as a museum and bookstore on 26 May 2006. Behind it, where the stucco has been removed, a wall of the original petrified wood shows. As read on 31 October 2026, the park’s visitor-centre services are running from the inn while the Painted Desert Visitor Center is under construction. ### Six hundred and fifty marks Newspaper Rock is neither a newspaper nor a single rock, the Park Service says, but a group of rock faces carrying over 650 petroglyphs, pecked through the dark desert varnish by ancestral Puebloan people who lived, farmed and hunted along the Puerco River between 650 and 2,000 years ago. With so many makers over so many years there is no single story to read; modern American Indian groups interpret the marks as clan symbols, spiritual meanings, calendar events, boundaries and migration routes. Unstable slopes keep visitors on an overlook, with free spotting scopes. At Puerco Pueblo, less than a mile north, a petroglyph marks the summer solstice with sunlight. ### Pictures and memories Asked what visitors may take from the park, the Park Service answers: pictures and memories. It is against the law to remove any natural or cultural resource, it says, including petrified wood, other rocks, plants, animals, pottery pieces, arrowheads and Route 66 debris, and even picking flowers. The wood in the park lies where nature left it, the Park Service adds; the largest concentrations are at Rainbow Forest, Crystal Forest and Jasper Forest, and the largest of all is the Black Forest. **The Relic** Agate House. On a small hill in the Rainbow Forest, the National Park Service says, stands an eight-room pueblo built of petrified wood: medium and large pieces carried up the knoll, set in mud mortar and chinked with smaller chips of the same stone wood, in walls a foot thick. Ancestral Puebloan people built and lived in it sometime between 1050 and 1300, probably as a single family’s year-round home, near their fields and the wood deposits, and it may have served as a meeting place too. It was excavated and partly rebuilt from its own fallen stone in the winter of 1933 to 1934 by a Civil Works Administration crew under the archaeologist Cornelius B. Cosgrove Jr., and the Park Service notes that the reconstruction is not a completely accurate copy. It asks visitors not to sit, stand or lean on its walls. ## Getting there How to get there. By car, from Interstate 40. Westbound drivers take Exit 311, drive the 28 miles through the park and continue on Highway 180 for 19 miles to Holbrook; eastbound drivers take Exit 285 into Holbrook, follow Highway 180 for 19 miles to the south entrance and drive north through the park back to the interstate, the Park Service says. Driving the park road without stopping takes about an hour; most visitors spend two to three hours. When to go. The park is open every day of the year except Thanksgiving and Christmas Day, the Park Service says, and in winter opening may be delayed until the roads are safe. Arizona keeps Mountain Standard Time all year. The monsoon season runs from 15 June to 30 September, with afternoon thunderstorms, lightning and flash floods; low morning and evening light brings out the colours of the badlands. What to arrange ahead. There are no campgrounds in the park; the Park Service issues free permits for wilderness camping at least a mile from the trailhead, from the Painted Desert Visitor Center, the Painted Desert Inn and the Rainbow Forest Museum. Food is limited to a diner, a convenience store and small counters, and the nearest other food is about 15 miles away on I-40 or 18 miles away in Holbrook. Agate House is a 2-mile round-trip walk from the Rainbow Forest Museum parking lot. Safety. The State Department’s travel advisories cover other countries, so none applies here. The hazards are the park’s own: sun, heat, summer lightning and flash floods; the Park Service warns that in a storm a visitor is often the tallest thing in this landscape. In an emergency, dial 911. ## Common questions #### Where is Petrified Forest National Park? Petrified Forest National Park is in north-eastern Arizona, on Interstate 40 east of Holbrook. A 28-mile road runs through it from the Painted Desert at the north end, at I-40 Exit 311, to the Rainbow Forest at the south end, on Highway 180, the National Park Service says. #### How did the wood at Petrified Forest become petrified? More than 200 million years ago logs washed into a river system and were buried quickly, the National Park Service says; over thousands of years silica from volcanic ash soaked into the wood and crystallised as it decayed. The petrified wood at Petrified Forest National Park is almost solid quartz, coloured by iron, carbon and manganese. #### Why do the logs at Petrified Forest look as if they were cut? As the Colorado Plateau rose, from about 60 million years ago, the buried quartz logs of Petrified Forest National Park came under such stress that they broke like glass rods, the National Park Service says. Quartz fractures cleanly, so the logs split at even intervals and look as if they were cut with a chainsaw. #### Can you take petrified wood from Petrified Forest National Park? No. The National Park Service says it is against the law to remove any natural or cultural resource from Petrified Forest National Park, including petrified wood, other rocks, plants, animals, pottery pieces, arrowheads and Route 66 debris, or to pick flowers. Its answer to what visitors may take is pictures and memories. #### Is Route 66 in Petrified Forest National Park? Yes. The National Park Service says Petrified Forest National Park is the only park in the national park system containing a section of historic Route 66. Weathered telephone poles mark the old roadbed, and a 1932 Studebaker sits where the highway, established in 1926, once crossed the park. #### What is Agate House at Petrified Forest? Agate House is an eight-room pueblo built of petrified wood and occupied between 1050 and 1300 at Petrified Forest National Park, the National Park Service says, probably as a family’s year-round home. It was partly reconstructed in the winter of 1933 to 1934 and is reached by a 2-mile round-trip trail from the Rainbow Forest Museum. #### What is Newspaper Rock at Petrified Forest? Newspaper Rock, in Petrified Forest National Park, is a group of rock faces with over 650 petroglyphs made by ancestral Puebloan people along the Puerco River between 650 and 2,000 years ago, the National Park Service says. Visitors view them from an overlook with free spotting scopes, since the slopes around the rocks are unstable. #### When did Petrified Forest become a national park? President Theodore Roosevelt proclaimed Petrified Forest National Monument on 8 December 1906, in the second group of national monuments created under the Antiquities Act, and Congress redesignated it Petrified Forest National Park in 1962, the National Park Service says. What to pack: the Desert & salt kit ## Related places Bisti/De-Na-Zin Wildernessalso in Deserts · about 230 km away Archesalso in Deserts · about 440 km away Joshua Tree National Parkalso in Deserts · about 580 km away The Grand Canyonalso in The US National Parks · about 250 km away Mesa Verdealso in The US National Parks · about 290 km away Notes on sources. Petrified Forest National Park is in the United States, so no State Department advisory applies. The National Park Service’s Petrified Forest pages (nps.gov/pefo), read directly on 31 October 2026, supplied this entry: the home page and linked-data file (badlands, grasslands, one of the world’s largest and most vivid collections of petrified wood, more than 200 million years, ancestral Puebloan sites, historic Route 66, the visitor centers’ coordinates); Frequently Asked Questions (the 1906 monument group and the 1962 park, over 200,000 acres and the 2004 expansion to 218,533 acres, the law on removing resources, the 28-mile drive and its timing, the interstate exits, the badlands and bentonite, the 20 million years of tree deaths, the early dinosaurs, the petroglyphs and the solstice marker, the largest wood concentrations, the inn’s cracks and back wall, camping and food); A Brief Administrative History (the 1906 proclamation and its words, Herbert Lore and the Stone Tree House, the 1936 purchase, the Civilian Conservation Corps remodelling of 1937 to 1940, the 1963 closure, the 1987 landmark listing, the 2006 reopening, Fred Kabotie’s murals); Petrified Wood (quartz, colours, burial, silica, crystals, Araucarioxylon arizonicum, the glass rods and the plateau’s uplift); Historic Route 66 (the only section in the national park system, 1926, the telephone poles); Places to Go (the 1932 Studebaker); Agate House; Newspaper Rock; Park Hours (open every day except Thanksgiving and Christmas); Current Conditions (winter delays, the monsoon season); and the alerts file (the visitor-centre services at the Painted Desert Inn, as read on 31 October 2026). Fees are not given here; check the park’s Fees and Passes page. Written and fact-checked by SockMonkey.com. Last reviewed 31 October 2026.