I'll do it in smaller chunks........
The towns and regions of Cape Cod (CC)
Cape Cod is a sandy spit left behind when the glaciers retreated around 18,000 years ago. As the glacier left, it gouged up bits of sand and left some of it's ice behind to fill those holes with icy water. Today, we call them kettle ponds. I wonder about how much of the actual glacier water is still in those ponds. And, what would one find if one core sampled the silt below the water. You can see by looking at the photo below and Jespah's above, why people refer to the cape as if it were an arm, bent at the elbow. My parents live just North of the elbow. At the finger tips is Provincetown (P-town) and in the arm pit is Woods Hole.
Sand, in the face of ocean waves, sea winds and NorEasters, doesn't hold up. CC is eroding at several feet each year. Lighthouses have been moved inland. Roads (see photo below) and houses have fallen off the sea cliffs. Man made structures have been laid down to stop erosion and this has disrupted the natural flow of sand - see, the sand redeposits elsewhere along the CC seashore. In one spot, a barrier beach called North Beach, has been breached and remade over and over again over the last several hundred years. It protects a little baylette called Pleasant Bay in Chatham (photo below). The bay is difficult to navigate because the sand shifts all the time.