Cliffs result when heavy wave activity eats away at a hard slope of land.
Depending on the hardness of the cliff rock and the angle of the rock layers, a cliff may be a gentle slope down to the ocean or a dramatic steep drop or overhang.
If the layers of the cliff’s rock tilt upward as they reach the coastline, the former will most likely occur. If the layers tilt down toward the water, however, the waves will eat away at the base of the cliff, creating an indentation.
Sooner or later, once the waves erode enough rock at the base of the cliff, the rest of the cliff will fall into the ocean.