Cuestas in geology are ridges formed by gently tilted hard rock layers. Every cuesta has a steep slope where the rock layers are exposed on their edges, called an escarpment. Usually a hard rock layer also has a more gentle slope on the other side of the ridge called a 'dip slope'.

Two well-known cuestas in western New York and southern Ontario are the Niagara escarpment and the Onondaga escarpment, where the dip is about 40 feet per mile to the south. The escarpment edge faces north and runs roughly parallel to the southern Lake Ontario shoreline.