Places We Protect

Keystone Ancient Forest Preserve


Keystone Ancient Forest in eastern Oklahoma.
Keystone Ancient Forest Preserve Keystone Ancient Forest Preserve © by Mike Fuhr

Oklahoma's first and only forest included in the national Old-Growth Forest Network.



This ancient crosstimbers forest has survived ice, fire and drought where post oak and redcedar trees have aged from 300 to 500 years old making this forested area older than the United States itself. The crosstimbers ecosystem originally covered 30,000 square miles, stretching from Texas through Oklahoma and into Kansas, as European explorers made their way west.

The crosstimbers earned its name from settlers who found much of the thick forests impassable. Author Washington Irving passed through in 1832 and wrote of the "vexations of flesh and spirit" that set upon the travelers who he said felt as if they were "struggling through forests of cast iron."

Fortunately, the thick canopy and craggy terrain has prevented developers from fragmenting this ancient habitat for industry, grazing or agriculture. No cotton farmers cleared these rocky hills nor did woodmill workers harvest trees for chip piles and even wildfires couldn't swarm the bluffs.

That makes these 1,200 acres especially unique as around 80 percent of the ancient forests elsewhere over the crosstimbers range in Oklahoma has been cut away or otherwise transformed.


Limited Access

The preserve has limited access and is only open on select days.


Hiking hours are 7 a.m. to 2 p.m. on Thursdays and 7 a.m. to 6 p.m. on Friday, Saturday and Sundays.


Hiking trails, Old-Growth Forests, Wildlife, Migratory Birds


1,200 acres

Explore our work in Oklahoma

Forest Photos

Tag @conserve_ok on Instagram with your pics from the forested trails.

Thick forest of tree canopy.
Hiking trail through trees.
Wood duck standing on a tree branch.
Coyote trotting.
White-tailed deer camouflaged in the trees.
Cooper's hawk in a tree.
Racoon family sitting on a tree branch.
Bobcat camouflaged with fall colors.
Wild turkey
Hiking trail next to a bench.
Keystone Ancient Forest trail entrance.
Keystone Ancient Forest Preserve Keystone Ancient Forest Preserve © by Mike Fuhr

Conservation Easements

The Nature Conservancy held a management agreement over the preserve since 2002 when the property was originally purchased by the City of Sand Springs. However, in March 2015, the City donated a conservation easement to The Nature Conservancy to ensure the land will stay intact as a natural area.

Until now there has been no park or preserve dedicated to these historic forests like these and conservationists estimate the vast majority already has been destroyed. The Nature Conservancy hopes that this preserve will do for the ancient crosstimbers what the Joseph H. Williams Tallgrass Prairie Preserve north of Pawhuska has done for tallgrass ecosystems.


  • From 209th West Avenue (Prue Road) and Highway 64 / 412 exit - Travel north along Prue Road approximately 2 miles. The entrance is directly across from the second cell phone tower and features a large sandstone and black iron gate.

    Click here for a map.

  • Open Thursday 7am-2pm, Friday-Sunday 7am-6pm

    Property is locked promptly at closing time.

    Dogs allowed the 1st Saturday & 3rd Sunday of each month.




    Just a 20 minute drive west of Tulsa, these trails offer a great way to recreate and envision the past! Trails are simple to navigate with markers showing easy to moderate ratings at this time. Hikers are advised to stay on the trails for your own safety, and to reduce visitor impact. Hiking is recommended for ages 4th grade and older! 

    Click here for a trail map.

    Trail Guides

    Volunteer trail guides help staff the parking lot and monitor each hike event. You can hike alone, or if there are enough trail guides available and you choose to, someone may hike with you to help interpret the forest landscape and this interpretative project in the making!


    No reservations are needed.  Pets are allowed on select hike with your dog days. Wear comfortable hiking attire, sun screen, and bug spray if you would like. 

    Hike dates are subject to change due to weather. Please see the Keystone Ancient Forest Facebook for current updates and cancellations.

Find More Places We Protect

The Nature Conservancy owns nearly 1,500 preserves covering more than 2.5 million acres across all 50 states. These lands protect wildlife and natural systems, serve as living laboratories for innovative science and connect people to the natural world.

See the Complete Map

Support Old-Growth Forest Conservation in Oklahoma

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