Cool idea for a road trip: Travel to one of the 20 least visited national monuments in the U.S. as documented by the Chicago Tribune. Below is one of the prettiest, and also the most obscure: Aniakchak National Monument and Preserve in Anchorage, Alaska. Last year, it boasted roughly ... 14 visitors. From New Mexico to the Virgin Islands, check out more of our favorites after the jump.

Hovenweep, in Utah and Colorado, features some of the United States' original ghost towns, dating back to the 13th century.

Visit 700-year-old caves and amazing wildflowers displays in Tonto, Ariz.

Hey, we never said continental. Buck Island Reef in the Virgin Islands has tons of amazing stuff in its diverse ecosystem.

The El Morro bluffs in New Mexico are carved with thousands of Puebloan, Spanish and American messages.