Strange stone tunnels and chambers, perhaps prehistoric, have been found in Leyden, Wendell, Pelham, Montague, New Salem, Whitingham, VT and throughout New England. Who built these structures and when? Why? Ashfield stonemason Jim Vieira has been exploring local stone chambers for years as a member of the Northeast Antiquities Research Association, which has studied these structures for 60 years. He describes the stone ceremonial landscape of New England, carbon-dating evidence and historical texts. His slides document local sites and others in New England, and he discusses what they represent and who may have built them – giants.