Morton Park is Plymouth's main green escape, a large wooded area with ponds, trails, and seasonal swimming spots. It is a useful counterweight to the town's history-heavy waterfront, especially if you want trees and fresh water instead of monuments.
The park works well for families, picnics, and short walks when you have a car or bike. It is less compelling as a destination in itself, but it rounds out Plymouth nicely by showing how quickly the town gives way to woods and kettle ponds.