Safe Halloween in Yarmouth Port Several venues around Yarmouth Port Common on Route 6A will offer treat-or-treat and safe Halloween activities on Oct. 31 from 4:30 to 7 p.m. Participating are the Captain Bangs Hallet House, Gorey House, Thacher Hall, Winslow-Crocker House and the Chapter House. The Yarmouth Port Library also will offer a spooky story at 5:30 p.m. in Thacher Hall. All events are free and open to all ages. No Registration needed.