Boston Neck is first fortified.

[1631] The 40-yard wide isthmus that sometimes floods at high tide is fortified to protect the town from attacks by Native Americans. Samuel Adams Drake later muses, “Whether what constituted old Boston was at one time an island, or was becoming one by the wasting forces of the elements, is an interesting question for geologists.” The neck, subsequently described by George Weston Jr. as the “stem of the pear” of the Shawmut Peninsula, is fortified by a gate across it in 1640 that keeps travelers from entering or leaving the town after a certain hour. Another fortification is built there in 1710* and a third in 1774.* Some type of barrier or guard post is maintained until 1832.