Places We Protect

Keystone Ancient Forest Preserve


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

The Keystone Ancient Forest Preserve protects ancient oak and cedar crosstimbers that are hundreds of years old.



Ice? Fire? Drought? This ancient forest is made of tougher stuff than most people know. These hard-crusted trees, some of them 300, 400, even 500 years old, stand as a sage army of post oaks and redcedars, undisturbed, unyielding, less than 15 miles from Tulsa, marking the gateway from the deciduous forests of the East to the prairies of the West.

Some of these trees have had their tops knocked off by wind or broken by ice over the passing centuries. But they'd be here, lush in the spring, painted in the fall or bare in winter when visitors can see through the maze of branches over the high bluffs on windy days and watch cloud shadows chase sun streaks across the lake below.

Protected From Development

Fortunately, the craggy terrain has left developers unwilling or unable to tackle the area. No cotton farmers cleared these rocky hills. No woodmill workers harvested trees for chip piles. Wildfires couldn't swarm these bluffs. There was no clearing for grazing or crops or development, all of which have cut away some 80 percent of the ancient forests elsewhere over much of the crosstimbers' historic range across Oklahoma.

Crosstimbers Forest

While some would consider the area's beauty subtle, its history is anything but that. The crosstimbers originally covered 30,000 square miles, stretching from Texas through Oklahoma and into Kansas, and they were here when European explorers wandered through the state and when Indian tribes called it home. This forest was here before this was America.

The crosstimbers earned its name from settlers who found much of the thick forests impassable as Oklahoma Territory was opened for settlement. American writer 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."

Understanding The Impact

In many ways, the crosstimbers has suffered unnoticed declines for the same reason the tallgrass prairie suffered for years. In both ecosystems, the beauty is subtle. The post oaks survive in a drought-stressed land and don't show their age by growing wide and tall like California's ancient sequoias. At first glance, they don't look old.

Until now there has been no park or preserve dedicated to these historic forests. 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 Tallgrass Prairie Preserve north of Pawhuska has done for tallgrass.

City Partnership

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.

Owned and operated by the City of Sand Springs, the Keystone Ancient Forest Preserve totals over 1,200 acres and protects a prime example of cross timber woodlands, including some of the oldest known living eastern redcedars, aged at over 500 years.


Limited Access

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


The preserve is open for free hikes on selected days each month. To arrange a visit, please visit the City of Sand Springs website at or call the Sand Springs Parks and Recreation Department M–F, 8 a.m. – 5 p.m. at 918-246-2561. No pets allowed.


1,200 acres

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