ABOUT THIS SITE
Petrified Forest Park in Gilmer, Texas is one of East Texas’s most accessible public rockhounding destinations. Located in Upshur County in the heart of the Piney Woods, this park preserves a remarkable geological record of ancient plant life transformed into stone over millions of years. Collectors come specifically to find petrified wood and silicified wood specimens , organic material replaced by silica minerals through a slow geochemical process that preserves original structure in extraordinary detail.
The site lies within the geological context of East Texas’s ancient forests, where wood buried in sediment tens of millions of years ago was slowly replaced by groundwater rich in dissolved silica. Over time, the silica minerals crystallized within the cellular structure of the wood, producing specimens that are chemically identical to stone but structurally identical to the original tree. The result is Texas petrified wood that sometimes retains visible grain lines, growth rings, and even bark texture , a window into forests that existed long before humans walked the earth.
WHAT YOU’LL FIND
The primary target at Petrified Forest Park is petrified wood, ranging from small fragments perfect for display pieces to substantial log sections. Coloration varies based on trace mineral content during the silicification process: earthy browns and warm tans are most common, while pieces with iron content can display rusty reds and oranges. Some specimens show striking black or gray tones from manganese or carbon inclusions. The surface layer of specimens is often weathered, but a single clean break with a rock hammer frequently reveals brilliant interior color and preserved cellular detail.
Beyond petrified wood, collectors in the broader Upshur County region occasionally encounter silicified bark and pieces showing original knot structures or branch junctions. Quality varies across the site , patience and systematic searching of eroded slopes and stream-cut banks will yield the best specimens. Surface collecting after rain is particularly productive, when fresh erosion exposes new material.
GETTING THERE
Petrified Forest Park is located in Gilmer, Texas (Upshur County), approximately 100 miles east of Dallas. From Dallas, take US-80 east toward Mineola, then US-271 north toward Gilmer. From Longview, travel US-259 north approximately 25 miles into Gilmer. Gilmer is the Upshur County seat and has gas stations, grocery stores, and restaurants for pre- and post-trip needs. Use GPS coordinates 32.729°N, 94.946°W or search “Petrified Forest Park Gilmer TX” in Google Maps for turn-by-turn directions to the park entrance.
WHAT TO BRING
Even though the terrain is easy and family-friendly, come prepared for a productive field outing. Essential gear includes: plenty of water (East Texas humidity is no joke even in cool weather), sturdy closed-toe shoes or boots, and sunscreen. For collecting, bring a rock hammer and cold chisel to test and break surface specimens, heavy leather gloves to protect your hands, and a 10× hand loupe to examine silicification detail. Pack newspaper or paper bags to wrap and cushion specimens for the drive home. A small daypack keeps your hands free while you search.
BEST TIMES TO VISIT
Fall (October–November) and spring (March–May) are the sweet spots for rockhounding at Petrified Forest Park. Autumn is particularly productive: seasonal rains cause natural erosion that exposes fresh specimens, and falling leaves open up visibility across the ground. Temperatures are comfortable for extended searching. Spring offers mild weather and low humidity before the East Texas summer arrives in force. Summer collecting is possible but demanding , plan early morning starts and bring twice the water you think you need. Winter visits work well on dry days; bare deciduous trees actually improve ground visibility significantly.
SITE FEATURES
FREQUENTLY ASKED QUESTIONS
What will I find at Petrified Forest Park?
The park is known for petrified wood and silicified wood specimens , ancient logs and branches transformed by silica minerals over millions of years. Colors range from earthy browns and tans to occasional reds and grays depending on trace mineral content. Preservation quality varies widely: some pieces retain visible grain and ring patterns while others are more weathered fragments.
Is collecting free and open to the public?
Yes. Petrified Forest Park in Gilmer is a public park with free access and collecting permitted within posted guidelines. Always check current signage at the park for any limits on quantity or specimen size. Respect all posted rules and practice Leave No Trace , fill any holes, take only personal-use quantities, and leave the site as you found it.
What should I bring for rockhounding here?
Pack water, sunscreen, and sturdy closed-toe shoes , even on easy terrain, loose rock and roots can be hazardous. Bring a small rock hammer, chisel, and sturdy gloves for prying surface specimens. A hand lens (10× loupe) helps identify silicification quality. Bring paper bags or newspaper to wrap delicate pieces, and a field notebook to record where you found each specimen.
When is the best time of year to visit?
Fall (October–November) and spring (March–May) offer the most comfortable collecting conditions. Summer in East Texas brings heat, humidity, and heavy vegetation that can obscure surface finds. After autumn rains, freshly eroded specimens are often exposed on slopes and stream banks. Avoid visiting immediately after heavy rain when trails become muddy and slick.
🪨 ROCKHOUND CODE OF ETHICS
Fill all excavation holes. Take only what you can use. Leave the site as you found it. Respect all land ownership rules and permit requirements. When in doubt about collection limits, collect less and return another day.
MORE ROCKHOUNDING IN TEXAS
Texas is a geologically diverse state with rockhounding opportunities ranging from petrified wood in the Piney Woods to agate and flint in the Trans-Pecos desert. Browse all Texas rockhounding sites to plan your next collecting trip across the Lone Star State.