The Rainbow Bridge was on Depot Street and was the sixth bridges to be built over the Merrimack River at that one location. In 1803 the first bridge went in and lasted sixteen years until 1819 when it was swept away in a spring freshet. The bridge was rebuilt and opened the next year. It was only four years later in 1824, and again in 1839, that the bridge was lost and rebuilt. In 1848 the bridge was swept away for the last time. This time it was nine years before it was replaced in 1857. The Rainbow bridge was built and used for fifty years until 1907 when it was replaced with a new iron bridge. The iron bridge was the seventh and last bridge and closed in 1965. It was removed a years and a half ago.
