Filling of the Back Bay tidal flats

The Back Bay tidal flats were filled between roughly 1857 and 1882 to create the Back Bay neighborhood, converting mudflats into a planned Victorian-era residential and commercial district. The fill used earth and gravel brought in by rail from surrounding areas and produced streets such as Commonwealth Avenue and Boylston Street on land that had not previously existed. Major institutions now on former landfill include the Boston Public Library and many Back Bay landmarks.