The artificial grotto must go way back. It is often, but not always, sacred. There are the Lourdes grottoes in churchyards, suggesting timeless cave worship; there are handmade caves in museums and amusement parks, too, complete with crystals and stalactites. The inland United States boasts acres of religious concretions, mostly built by Central European immigrant clerics. Although, in their obsessiveness and imitation of natural landforms, these environments recall the Indian mounds often found nearby, this grotto art seems to have originated in Europe, with its cave architecture, shell temples, and follies. And, whereas anthropologists imagine the mounds to have been a communal effort, on the order of pyramids or cathedrals, the grottoes are typically the product of one inspired individual, with maybe a devoted helper.

This album, with photos by ourselves, illustrates some of the grottoes Suzanne Mercury and I have visited in the past 25 years.