Fodor's Expert Review Oregon Caves National Monument

Marble caves, large calcite formations, and huge underground rooms shape this rare adventure in geology. Guided cave tours take place late March through early November. The 90-minute ½-mile tour is moderately strenuous, with low passageways, twisting turns, and more than 500 stairs; children must be at least 42 inches tall to participate. Cave tours aren't given in winter. Aboveground, the surrounding valley holds an old-growth forest with some of the state's largest trees, and offers some excellent and generally uncrowded hiking.

GPS coordinates for the caves often direct drivers onto a mostly unpaved forest service road meant for four-wheel-drive vehicles. Instead, follow well-signed Highway 46 off U.S. 199 at Cave Junction, which is also narrow and twisting in parts; RVs or trailers more than 32 feet long are not advised.