Carlsbad Caverns Deep Dive
Carlsbad Caverns in southeastern New Mexico contains the Big Room — a single chamber of 33,210 square metres, the largest cave room in North America. The cave was a national monument from 1923, a national park from 1930, and is a UNESCO World Heritage Site.
Sulfuric acid speleogenesis
Carlsbad and the other Guadalupe Mountains caves (Lechuguilla, Slaughter Canyon, Spider Cave) formed by a process distinct from ordinary karst dissolution. Hydrogen sulfide rising from oil-bearing deposits below the Capitan Reef limestone reacted with oxygenated groundwater to produce sulfuric acid, which dissolved the limestone from below. This produces caves with abundant gypsum and far more rapid dissolution than carbonic acid speleogenesis.
The Big Room
A 1.25-mile loop on a paved walkway around a chamber 1,200 m long, 190 m wide, and 78 m high. Major formations include the Bottomless Pit (140 m deep), the Hall of Giants (cluster of huge columns), the Painted Grotto (helictites), and the Top of the Cross at the chamber's intersection.
Bat flight
A colony of approximately 400,000 Brazilian free-tailed bats inhabits the cave May-October. Their evening departure at sunset is one of North America's great wildlife spectacles. A natural amphitheater at the cave entrance has tiered seating.
Discovery
Apache people knew of the cave for centuries. The first documented Euro-American descent was made by 16-year-old Jim White in 1898, who explored alone for years before the cave was "officially" found. White's accounts were initially dismissed until photographer Ray V. Davis's 1922 images confirmed his descriptions.
Visiting
The Big Room is wheelchair-accessible via elevator from the visitor centre — 247 m straight down. The Natural Entrance is a 1.25-mile descent on foot through the natural cave opening. Ranger- led tours of less-visited sections require advance booking.
Practical
Open daily except major holidays; reservations required. Cave temperature constant 56°F / 13°C. The Big Room is fully lit; off- trail tours require boots and helmet.
Explore on the map
See Carlsbad Caverns on the interactive map.