I was born and raised just a stones throw from Revere. I miss Kelly's Roast Beef. Great Lobster rolls too.
I was not into metal detecting when I lived there, but I wish I did. If you go about 40 mins. north up Rt. 95, there are really old sites in Cape Ann. Up toward Boxford, Georgetown, Newbury, Newburyport. Check out Google Earth and you'll see the old fields up there. I'm sure you can get permission, the people up there are really nice.
There is an old Snuff mill in Newbury AKA Byfield. There is a waterfall there and we used to dig really old bottles out of there. I was there a few months ago and it's still there, just not in use. The family is really nice that own it, and I went trout fishing.