After leaving Santa Fe, the highway to Carlsbad is very very boring. Flat, straight roads, the only thing of interest is the massive trains pulling across the horizon. We finally arrived in Carlsbad, and entered the National Park. All we knew was that there were caverns / caves here. The park road ended at the Visitor Center, nothing else in sight. Where are the caves? Well of course they are underneath us. 75 floors below us (754 feet). We opted to take the hike in Natural Entrance, 20 percent grade for 2 kilometres. Once in the “Big Room” at the bottom you are truly amazed. These caves are massive, huge, gargantuan. Words cannot express how big they are. We spent a further 1.5 – 2 hours walking around the big room (another 2 kilometer loop). There are also probably another 5 miles of caves that are not open to the public. We highly recommend this stop if you are in the area. And of course there is an elevator to take you back up to the surface.!!!! Bonus.