Carlsbad Caverns National Park is a national park in the United States in the mountains of southeastern New Mexico. Carlsbad Cave is the primary attraction which is open all round the year except for some annual national holidays. Tourists have an option of hiking on their own on a natural track or using an elevator designed for the visitor center. The Carlsbad Cavern included a large cave chamber called the Big Room and is the fifth largest chamber in North America. It is the twenty-eighth largest in the world.