Cannon Beach extends south from Tillamook Head and Ecoloa State Park. It's best known, visually and geologically, for Haystack Rock, a very large sea stack located just offshore, yet still accessible during low tides. Haystack Rock is Columbia River basalt, extruded into the surrounding sediments as the flows reached the former coast and then subsequently exposed by erosion.
Cannon Beach seems to be several communities stretched out along the shore. The northern end is very low - a barrier beach associated with the mouth of Ecola Creek. But much of the rest of the town to the south lies on somewhat higher ground behind a modest bluff, although I'm not sure if this is a marine terrace or just old dunes.