Entering the lower reaches of the Slot is abrupt and impressive. Basically, there is a crack in what is otherwise a sheer wall. It's perhaps 25 ft deep and varies in width from a few feet as seen here to less than one foot. At its narrowest, one has to remove packs, cameras, etc. and shuttle sideways for a few meters where the Slot widens again. In other parts of Borrego, there are formations identical to the Slot except that the roof is sealed. These mud caves, located near Arroyo Tapiada to the south, are even more impressive.... Perhaps next time.