West of Ronda, marked on most road maps and easily located with a big sign from the road to a parking area with info boards.
A series of uneven and slippery-when-wet stone steps lead from the car park up to the cave entrance and ticket hut (which also serves drinks in season), where there is a covered waiting area. The entrance fee varies by total group size - 8 euros pp reducing to 7 if there are more than 15 people on a tour. The maximum tour size is 25.
By 4pm, a group of 20 or so had gathered and the entrance was unlocked so we could all move into a foyer area, where the guide lit and distributed battery lanterns for the visitors, and filled his paraffin lamp. I had a small head torch which came in handy, though your own torch is far from essential. The tour was mainly in Spanish with a few words of English added; one of the other visitors was leading a group of Scandinavian and German tourists, and he kindly translated a fair amount of info into multiple languages for everyone.
The tour lasts just over an hour, progressing through the cave system looking at the rock formations, explaining history and discovery, with fabulous cave paintings along the way. The end point is the painting of a huge fish .... then a faster walk back along the same route to the entrance.
There are lots of steps within the caves, so I would recommend to reasonably sure-footed visitors. On the way back, we crossed with the next tour starting .... which included family groups, one with children of around 2 and 5 years, and another with screaming baby in papoose .... the latter changed their minds and left .... it's really not a visit for little ones imo.
Please note - no photography past the entrance area, you will be asked to leave if you try to sneak a few shots. This may be to keep the light levels reasonably constant, but also repeated camera flashes would have ruined the ambience of the visit.