Boston's changing shoreline
Maps from research by Nancy Seashoals & Norman Leventhal Map Collection
Discovery of the Fishweirs
5,300 years ago, in what is now Boston’s Back Bay, Native people built fishweirs in tidal flats to catch alewife, smelt and salmon. These four-foot high, fence-like structures were woven of alder, willow saplings and brush wattling and were made of over 65,000 wood stakes.
Archaeological evidence discovered during subway excavation and building construction over the last one hundred years indicates that fishweirs were built over a 1500-year period in tidal marsh now located 28 to 40 feet below the Boston Common and the Back Bay.