Crafton lies on a sloped alluvial plain of the San Bernardino basin.
South and east of Crafton rise the Crafton Hills, a low, rolling set of hills created by about ten active[REF][REF] normal dip-slip faults collectively called the Crafton Hills fault zone[REF] or the Crafton Hills Horst-and-Graben Complex[REF] which stretches between the San Jacinto fault and the San Andreas Fault.