David Bear, Post-Gazette The setting sun creates a halo around the pinnacle of a hoodoo at Kasha-Katuwe Tent Rocks National Monument in New Mexico.

By David Bear, Pittsburgh Post-Gazette

SANTA FE, M.M. -- If you're in Santa Fe and have time to explore south of the city, check out Kasha-Katuwe Tent Rocks, a remarkable geological formation 40 miles to the southwest along Interstate 25.

David Bear, Post-Gazette Two shaded hoodoos are silhouetted against the sunlit canyon walls of the monument. Click photo for larger image. More information Tent Rocks National Monument is open year-round for day use only. The self-enforced entrance fee is $5 per car. From Santa Fe, take the Cochiti Pueblo Exit 264 off I-25 onto NM 16. Turn right off NM 16 onto NM 22, and follow the signs to Cochiti Pueblo and the national monument. For information, www.blm.gov/nm or 1--505-761-8700.

Designated a U.S. National Monument by President Clinton shortly before he left office in January 2001, this Bureau of Land Management site encompasses 4,148 acres along the edge of a deeply eroded mesa that was built up about 67 million years ago by ash and rock spewed from an active volcano seven miles away.

Over eons, a deep, slot canyon was worn into the 1,000-foot-high mesa, with contoured walls sculpted into smooth-sided ravines. The thick layers of gray pumice are interspersed with beige-and-pink-colored rock along the cliff faces.

In many places, as the pumice was gradually eroded away by rain and wind, harder, embedded boulders were exposed. With these stony caps protecting the softer materials beneath them, erosion produced hundreds of conical-shaped mounds, or "hoodoos," some up to 90 feet high.

These formations, which dot the landscape like giant, helmeted chessmen, lie on the lands of the Cochiti Pueblo, whose people regarded them as sacred. Kasha-Katuwe means "white cliffs" in the traditional Keresan language of the Pueblo.

Apart from the main parking lot and scattered picnic sites, the facilities consist of two hiking trails. The 1.2-mile-long Cave Loop trail meanders through a maze of manzanita shrubs around the base of the mesa.

The more challenging Canyon Trail is a 1.5-mile, one-way trek up into the narrow slot canyon. A steep, stepped climb at the end leads to the mesa's brow, which affords excellent views of the Sangre de Cristo, Jemez and Sandia mountains, as well as the broad sweep of the Rio Grande Valley.