Cathedral Cliff is a 5,810-foot (1,770-meter) elevation volcanic plug located on Navajo Nation land in San Juan County of northwest New Mexico, United States.

Cathedral Cliff is one of the phreatomagmatic diatremes of the Four Corners area, and with significant relief as it rises 400 feet (120 meters) above the high-desert plain.

Cathedral Cliff is the eroded remnants of a maar-diatreme volcano, formed when rising magma came into contact with country rock saturated with groundwater.

Subsequent erosion has removed 500 to 1,000 meters (1,600 to 3,300 ft) of overlying sediments to expose the deeper diatreme,[6] including the rarely-exposed diatreme-maar transition zone.

[8] Precipitation runoff from this feature drains into Dead Mans Wash, which is part of the San Juan River drainage basin.