1
Upton Cave
MA
In the center of New England, a landscape formed by very old orogenies and the glaciers of the last Ice Age, only very few and small natural caves exist. The rocks are gneiss, granite, marble and slate. The caves are tecto... showcaves.com
3
Nashoba Brook Stone Chamber
Acton,
MA
The Nashoba Brook Stone Chamber is an L-shaped, man-made room, 3.35m long, 2.74m wide and at its highest point 2.74m high. It is constructed of local stones of extraordinary size, the ceiling is constructed by only five ab... showcaves.com