About Petrified Forest National Park
Arizona's Petrified Forest National Park, located in the Navajo and Apache counties in Northeastern Arizona, features some interesting geological formations. Most commonly found rocks are vast deposits of petrified wood, known today as Arizona's state fossil. The park covers over 200,000 acres of desert land.
Due to its rich history from the Mesozoic era, and with the early inhabitants discovering petrified wood, the forest was first declared a National Monument in 1906 to protect this rare fossilized wood, and later designated as a National Park in 1962. Today, it draws 800,000+ visitors each year, from hikers, rockhounds, hobbyists, and tourists, making it one of Arizona's most popular outdoor destinations.
The park has a rich history of wood turned into mineral stone through a process known as fossilization. And one can find other varieties of sedimentary rocks, such as mudstone, bentonite, and sandstone. The park is open every day, except on Christmas Day, and works with Mountain Standard Time.
What Can Be Found in Petrified Forest National Park
- Petrified wood: What you'll mostly find in this area are deposits of petrified wood, which early inhabitants are recorded to have used for stone tools during the Ice Age. Around 200 million years ago, during the Late Triassic Epoch of the Mesozoic period, tall conifer trees grew near waterways. Many of these trees were eventually knocked down by severe flooding and buried under sediments rich in volcanic ash. Over time, groundwater dissolved silicate minerals from the ash and carried them into the buried wood, forming quartz crystals. These crystals, infused with traces of iron oxide and other minerals, combined with the silicate to create the colorful petrified wood we see today in a variety of shapes and sizes. Much of this petrified wood still comes from ancient conifer trees. Today, people visit this park for fossil research and to find petrified wood.
- Bentonite: Also known as Mudstone, it is a clay product made from volcanic ash decomposed from sedimentary rocks into a plastic-like clay. Found in the Blue Mesa trails in this forest, it is made from compacted clay and particles of sand or an accumulation of mud, silt, and other sediments in flood plains like this forest. Usually used for pottery, sealing materials, and other purposes.
- Sandstone: A common find here is sandstone, a kind of sedimentary rock made from sand-sized mineral particles. Usually used in constructions and sculpting due to its porosity and hardness.
Petrified Wood
Bentonite
Locations of Petrified Forest National Park
Rockhounding itself isn't permitted in the National Park, but you can still explore the visitor trails to view petrified wood. Be sure to stay on the marked paths to avoid damaging the grasslands or disturbing wildlife habitats.
Trails to Explore:
- Painted Desert Rim: A scenic 1-mile trail where you'll see petrified wood, sandstone, mudstone, and a variety of wildlife.
- Puerco Pueblo: This trail holds history for housing a community 200 million years ago. You will find ruins of villages from this era, and petroglyphs carved by the former inhabitants of the community.
- Blue Mesa: The Blue Mesa trail is a mile walk where you can find bentonite clay and deposits of petrified wood. There are also other animal fossils present in the sedimentary layer.
- Crystal Forest: A 0.75-mile walk that reveals petrified wood deposits. You can start from the crystal forest parking area.
- Tawa Trail: A 1.2-mile walk in the grasslands, you might see petrified wood or bentonite, but you should take in the scenic view.
- Giant logs: A 0.6-mile walk to find colourful petrified woods and logs.
- Long logs: a 1.6-mile walk starting from the Rainbow Forest parking area, where you can find petrified wood.
- Agate house: A 2-mile walk where you will find archaeological artifacts left behind by former inhabitants from 700 years ago.
The park can be accessed via Interstate 40, 25 miles west of Holbrook, Arizona, and a 3-hour drive from Phoenix. The park is usually open from 7 am to 7 pm.
Recommended Gear and Tips
Recommended Tips
- Know the Laws: The laws here are quite different. The forest is managed by the National Park Service. If you are going rockhounding, know that it is illegal to take petrified wood from the park. It is solely for sightseeing and enjoying the beauty of the park, or for research purposes.
- Stay on trails: You cannot veer off the trails marked for hiking by visitors. Stay on the marked trails to avoid damaging the grasslands or disturbing wildlife habitats.
- Ask Questions: Before setting out on the trails, stop by the visitor center for maps and safety tips. Take the opportunity to ask the staff where to spot petrified wood and bentonite, which trails best match your interests, and what rules apply within the park. The staff are always ready to help, and the guidance you get can make your visit safer and more enjoyable.
- Pets and Bicycles Rules: Pets are allowed, but they must remain on a leash. Also, keep in mind that bicycles and motorbikes are not allowed on the trails, except on the half-mile access path that connects the Long Logs and Agate House Trails.
Recommended Gear
Before going to the park, here are some items you should take along with you:
- Camera: Since collecting rocks isn't allowed in the park, bring a camera to capture photos of petrified wood, bentonite, or any other interesting finds along the way.
- Comfortable Wears: You will be walking around a lot, so wear clothes you are comfortable in. And wear comfortable shoes for hiking on the trails.
- Water and Snacks: Since it's going to be a long walk, be sure to bring water and snacks to stay refreshed while exploring the forest.
- Guide and Maps: You can stop at the visitor center for maps, geology guides, and updated trail information that will help your tour.
Recommended Gear
Final Thoughts
Petrified Forest National Park is more than just a field of fossilized trees; it's a glimpse into Arizona's prehistoric past, showcasing a unique combination of geology, history, and desert beauty. Whether you're there to marvel at beautifully-colored petrified wood, hike through the Painted Desert, or study sedimentary formations, the park is a must-see destination.
Other Rockhounding Sites in Arizona
While collecting petrified wood and bentonite is not permitted at the Petrified Forest, Arizona offers other opportunities for rockhounding and rock collecting:
Guidebooks For Arizona
Arizona is famous for its petrified wood and beautiful gemstones. If you want to dive deeper into the state's unique rockhounding history and gemstones, these guidebooks are excellent resources