Volcanic rock structure

Rock your world at Fort Rock Natural Area

Photos and Story by Greg Johnson, ActiveLifestylesNW.com travel writer

The fortress-like rock walls of Fort Rock loom over the surrounding flat, barren landscape.

Fort Rock, located about 70 miles southeast of Bend, was formed an estimated 70,000 to 100,000 years ago when basalt magma rose to the bottom of an ancient lake. Hot lava and ash formed a saucer-shaped ring of molten rock and volcanic ash.

volcanic landscape
Inside the Fort Rock caldera.

Early American Indians canoed to what was then an island on the estimated 900-square mile lake more than 9,000 years ago. Desert winds apparently crashed against the side of the now-dry lake to create the present day huge opening on its south side.

Ancient Native American petroglyphs are etched on the towering walls of the enormous caldera. Visitors can explore the caldera on a 1.1 mile trail into Fort Rock State Natural Area.

Other interesting geological oddities near Fort Rock are Hole-in-the-Ground, Fossil Lake and Crack-in-the-Ground.

For information on Fort Rock State Natural Area, go to www.oregonstateparks.org. For information on the homestead museum, contact Fort Rock Valley Historical Society, 541-576-2251 or email frmuseum@centurylink.net.

Huge rock structure
A giant rock structure dominates the landscape near the west side of the caldera.