A remnant of an ancient volcanic explosion, Kilbourne Hole was designated a National Natural Landmark in 1975. This crater can be found in a desert basin between the Potrillo Mountains and the Rio Grande in southern Dona Ana County. Kilbourne Hole is roughly elliptical in shape, and is known as a Maar — a pit or depression caused by a volcanic explosion with little material emitted except volcanic gas. The crater is between 24,000 and 100,000 years old, and measures 1.7 miles long by well over a mile across, and is hundreds of feet deep.
Kilbourne Hole has many unique minerals remaining from the eruption. The crusts of the Kilbourne Hole volcanic bombs — objects blown from the volcanic vent in a near plastic state — are dull black or brown, but when broken open they often reveal a brilliant, sparkling yellow and green interior of olivine glass granules.
Hiking, geologic interpretation.
None. Restrooms and drinking water are not available.
Location / Access
From Interstate 25 take the Vado Exit (10 miles south of Las Cruces) and NM 227 west 3 miles to NM 28. Take NM28 south (left) 2 miles to Dona Ana County Road (CR) B008. Take CR B008 west (right) 11 miles to Dona Ana CR B004 and turn south (left). Drive 6½ miles to railroad tracks. Turn left and cross railroad. Turn west (right) on Dona Ana CR A017 and drive for 7 miles to Dona Ana CR A011. Turn west (right) and proceed 8 miles to Kilbourne Hole. Kilbourne Hole is on the right, past the big tan dirt bank.