Cape Cod is richly supplied with walking trails and wildlife refuges of all kinds. One I see quite often but had not paid much attention to is the Dead Neck Trail, which accessible from the Mashpee Town Beach parking lot. It's not very long, just a mile and a half, but because most of it is soft sand it can be challenging.
Dead Neck runs between the dunes and the marsh, giving the walker a nice view of both. Because the dunes block the sea view it can feel pretty hot in the trail in the middle of the day, but the discomfort of heat is offset by the relative solitude of the trail. Once past the boardwalk to the beach you will seldom encounter another person. The only sounds will be birds. I had the amusing experience today of hearing a mockingbird imitating sea bird calls.