There is a lot going on in this photo. In the center, of course, is the “Love Rock,” a stalactite/stalagmite pair that is about to (geologically speaking, of course) form a column. But you can also see pipe organ-like flowstone formations in the rear and to the left, and to the right are some curtains. The stalactite part of Love Rock is also a curtain, or at least began as one.
I’m not completely clear on the difference between curtains and draperies, and at times I’ve seen the two used interchangeably, but as best as I can tell draperies are the smaller versions seen on flowstone stalagmites or beneath canopies, while curtains are much larger and hang directly from the ceiling. Curtains form when water doesn’t drip directly from the ceiling but flows down a slanted ceiling, forming a path of sediment that successive water drips follow. Draperies, on the other hand, are the result of water flowing over overhangs. This is, at least, the way I have used the terms here.