Visitor’s center below. Pay there, and then follow the signs outside to the cave’s entrance.
Free self guided tours in Carlsbad Caverns this weekend, so I don’t remember the exact price. Maybe $15 to see King’s Cavern and the Big Room, self-guided.
If passing through west Texas or southern New Mexico, this needs to be added to must see list for 4 hours.
Bring an extra shirt. In the caves there is dripping water (I hope) and cooler temperatures. Walking shoes are a must. Grippy is better, though I had no problem in sneakers.
Save your battery / film for the big room. Flash required for most people. But flash won’t help in Big Room. In there, you need a higher ISO or long shutter. Tripod would help but then you’re fighting for space w huge walking crowds. My phone camera worked ok (digital camera sensor technology is amazing), but I wonder how it would look w long shutter w DSLR and tripod.
This is important! Elevator back up is an hour wait with a large crowd. You can walk back up the way you came in, in same amount of time, but bring a map, so you don’t get lost and walk in circles. (5/5 self-rated for tourists)
Dog canyon campground is hour away in the Guadalupe Mountains National Park in adjacent TX, and there’s a narrow, winding road up the mountains to get there. I do not recommend driving at night. It has to be pitch black at night, and there is wildlife and grazing cows. But it’s a small campground at higher elevation. It’s cooler at night there. (3/5 self-rated for tourists)
To get there from Carlsbad, you pass Lincoln National Forest (no pictures), still in NM. There is a small vacation community at top of the peak. 85 degrees at white sands. 67 degrees at the peak.