Well, worth the 35 minute or so drive from Monterrey. Pass through a semi-industrial area but then the scenery and natural setting takes over and is quite nice. Highly recommend visiting these caves which are accessible by walking, but it's a pretty tough uphill walk, so I would suggest taking the cable car, which is referred to here as a funicular. The caves are magnificent, but be prepared to walk about 750 steps up and down. Guide was excellent, even though I did not understand everything he said, since I am an English speaker with limited Spanish comprehension.
Well, worth the drive time and thoroughly enjoyed the visit! read more