Tewksbury
Tewksbury has a segment of the Bay Circuit Trail along the Merrimack River, along with an assortment of other green spaces and trails.
Below is a Google map of Tewksbury that you can explore.
Tewkbury Trails
Trail maps for Tewksbury from town web site.
Tewksbury Conservation Commission
Town of Tewksbury Conservation Commission
All Trails
A link to All Trails extensive trail guides (membership may be necessary)