Excellent fishing spot if you have the proper boat, it is quite the haul depending on where you're coming out of. You name it, it swims out at Stellwagon.
An 842 square mile underwater ledge, that was designated a Marine Sanctuary in 1992. Great whale watching destination, and an even better fishing destination. It's the open ocean, so if it swims in the Northern Atlantic, it's probably at Stellwagon as well.