Definitely a nice spot for a visit. We came late in the evening, about 30 min after sunset just before it was getting dark - and no one was there, apart other overlanders :) Guy came to collect 40+25 pesos per person for camping and entry.
The next morning, it was super windy and dusty (and cold), but around 8:30 the sun came out and it was nice. We had the place basically to ourselves until 10:30 :)

Blog: Wedding Travellers

Place: Hierve el Agua

Visited: January 12th, 2018

Location: 16.866852, -96.276503