Carlsbad Caverns is an absolute must-see for anyone visiting Southwestern USA. Located in the Guadalupe Mountains in New Mexico, this fabulous cavern is an unforgettable scenery through one of the largest “chambers” in the world, the Big Room. What makes Carlsbad Caverns a fun place to visit is the self-guided tour; it is indeed possible to take a (long) hike without a ranger inside the cavern. This allows visitors to explore the cavern at their own pace – unlike in Mammoth Cave National Park.
On the way to Carlsbad Caverns, we passed the Guadalupe Mountains National Park but did not have time to stop for more than the Visitor Center. It’s probably worth a visit if you allow a few days in the region. The caverns are located in this mountain range.
Natural Entrance Trail
While it’s possible to take an elevator down to the cavern, the best way is to hike the 1.25 mile “natural entrance”, which is the way that explorers took when they discovered the cave. The iconic path to the entrance (which is literally a hole) allows for great pictures. 
Hiking Big Room Trail: Practical details
The Big Room trail is 1.25 mile long and fairly flat. By combining it with the Natural Entrance trail, you’re engaged in a 2.5 mile hike which will take about 3 hours to complete. Most of the trail is flat, expect some really steep portion that are all equipped with a guardrail. Some parts of the trail are wheelchair accessible. It is not necessary to return to the entrance via the same trail, you can just take the elevator once you’ve finished the hike. The highlight of the trail is the Big Room, an impressive, huge cavern with millions of beautiful rock formations.
The wonderful world of Carlsbad Caverns Speleothems
Speleothems is the generic term for rock formations inside caverns such as Carlsbad. They form in limestone. Carlsbad Cavers presents an incredibly diverse concentration of speleothems.
The most famous speleothems are stalactites and stalagmites, because they are the most common, but one can admire many other types at Carlsbad Caverns such as “soda straws”. Soda straws are tiny “arrows” grouped together, they look like they will break at any minute and fall on your head.
Draperies or flowstones are another kind of speleothem. They look like … draperies? Seriously, it’s amazing what can millions of year and water and erosion can do. These are simply magnificent. Some of these have such weird shape that give the impression to be in the Alien’s belly. They look alive.
Stalagmites, including giant ones with a rather phallic aspect, are plenty. 
Stalactites sometimes meet stalagmites that meet soda straws. It’s a speleothem party!
One of my personal favorites: the swiss cheese asteroid – totally made this up as I couldn’t find the actual name! 