There are several ways to approach it: as a diversion during a long distance hike of the Long Trail, as a long loop using part of the Long Trail and Green Mountain Trail, or as an OAB approach starting on the Homer Stone Trail in Wallingford. Since it was winter, we opted for the shorter Homer Stone approach (about 7.0 miles RT, 1950' EG). The Homer Stone Trail ascends to the Long Trail at Little Rock Pond, starting out as a wide woods road and narrowing to a trail halfway up at an unbridged wet crossing of cascading Homer Stone Brook (tricky in winter or high water). From there, the Green Mountain Trail ascends steeply up a series of ledges which give way to some open viewpoints overlooking the pond 600 feet below (we had none on account of socked-in conditions). Had it been summer, we could have combined it with a dip in the pond or brook, or an overnight sleepover to the sound of water lapping stones (there are several primitive campsites on the pond). Although the trail skirts the true summit of the mountain, one can bushwhack 0.2 or so to the top where there is a little register jar tied to a tree, and a secret view ledge.
I'll be adding Green Mountain to my rarified "pretty mountains with swimmable alpine ponds-list", among such excellent destinations as Tumbledown Mountain/Tumbledown Pond (ME), Sargent Mountain/Sargent Pond (Acadia National Park, ME), Old Speck Mountain/Speck Pond (ME), and Lonesome Lake/Cannon & Kinsman Mountain (NH). That'll be a topic for a 2022 summer post. Stay tuned. --Paul-William
Thanks to: Green Mountain National Forest (land conservation & trails); Green Mountain Club (trails).