Carlsbad Caverns National Park in southeastern New Mexico is considered to be a natural wonder of the world. Recently, cavers surveying the limestone caverns formed over millions of years came across an unexplored chamber. It's the largest discovery at the park in decades.
The Big Room is hundreds of feet below the earth's surface. Stalagmites look like they've pierced up through the floor from below. It's visited by nearly 400,000 people a year. The park has been remapping an area of passages in the ceiling formations.
In October, caver and volunteer Dereck Bristol climbed 250 feet up into the three-dimensional maze with one of the parks technicians and made his way over to a limestone ledge.
"Once we were up on the ledge we found a passage going off from the top of that ledge which was unexpected," Bristol explained.
The two explorers climbed in, mapping the area as they went. Thirty feet and half an hour later the passage opened up onto a damp room about one hundred feet in diameter. It was filled with calcite crystals and unusual blue clay.
"There is a lot of flow stone that comes down out of the dome that crosses the room," Bristol explained. "Covering the flow stone were thousands of bat bones. "
The explorers have named the room Halloween Hall in honor of the auspicious night the discovery was made.