Black and white lantern slide of petroglyphs found in Parral, Mexico.

Black and white lantern slide of a rock formation with petroglyphs in Parral, Mexico.

Black and white lantern slide of petroglyphs found north of Zape, Mexico.

Black and white photograph of wooden archaeological rulers on a site of petroglyphs with shrubs and field grass in the background.

Black and white lantern slide of petroglyphs found in Parral, Mexico.