Calamint Hill Conservation Area (CHCA) is located on Calamint Hill Road North. There is a parking lot about .25 miles up the road on the left. Between CHCA, Princeton's Boylston Park, and the PLT Appell trails there are about 3.5 miles of trails connected together, consisting of three loops.
Thus is a quiet woodland trail with some great viewing areas into a large beaver pond from the East and West sides of the wetland. The East Loop features a pretty walk through a hemlock forest and then down to the viewing area, which is closest to the Heron Rookery. The West Loop features a vewing area as well, on the shore of the large beaver pond. Both viewing areas have been equippped with benches for viewing. The two areas are connected through a wetland, and bridges are being implemented (needed during high water periods).
The Appell property, which lies to the west of CHCA includes a nice Boulder Field, and a flat walk along an open forest that runs parallel to Calamint Hill North Road. this Princeton Land Trust property abuts Calamint Hill Conservation Area.
The trail through Boylston Park is also marked with blue blaxes and goes abut a quarter mile down to South Wachusett Brook which is quite pretty and with lots of wildlife through the different seasons.
The full map can be viewed here.