 Here the Post Road splits, with the oldest route (prior to 1704) following East Street in an arc around the old marshes until it meets Washington Street (Route 1A) south of the Dedham village center.The new road (in use by 1744) followed High Street to Court Street, and continued south along Highland Street and Elm Street, rejoining East Street south of Interstate 95.In Roxbury, the road turned down Roxbury Street and followed modern-day Centre Street around the edge of Fort Hill, crossing Stony Brook at a bridge in the location of the modern-day Jackson Square MBTA station.