Road. They were built in the 1920s (the Forsyth Way bridge replacing an earlier crossing) as part of Arthur Shurcliff's reconfiguration of The Fens, and rebuilt as concrete bridges with granite facing in 1979. A third footbridge at Evans Way existed in the early 20th century, but was gone by 1915. A replacement was designed during the 1920s work and finally built in 1939. The bridge was disassembled in 1979 with the other footbridges, but it was never rebuilt, possibly due to funding shortfalls created by Proposition 2½. North from Boylston Street in Charlesgate Park, the Muddy River is crossed by Ipswich Street, the Worcester Main Line railroad bridge, the Massachusetts Turnpike, two bridges carrying Commonwealth Avenue, Beacon Street, and Storrow Drive, as well as the elevated Bowker Overpass and its ramps. The west border of the Fens (where it meets the Riverway) is Brookline Avenue, which crosses the Muddy River on a wide bridge completed in 2016. Former bridges Along with the Evans Way footbridge, two road bridges are no longer extant. The Fenway originally crossed the Stony Brook canal at the Huntington Entrance on a five-arched bridge designed by the firm of Walker & Kimball. The outer arches were occupied by footpaths, allowing pedestrians to cross under the road. The bridge was faced with red brick ornamented with Milford granite; the archways were faced with patterns of colored glazed bricks. A small iron footbridge crossed the canal just north of the road bridge. The bridges were removed when the canal was filled in 1905; the road bridge was demolished with explosives. At the Beacon Entrance, a curved bridge crossed the Boston and Albany Railroad (and after the 1890s, Ipswich Street). Its south end connected to Boylston Street at Gaston Square, while its north end met Commonwealth Avenue. Although Richardson sketched designs for truss and suspension bridges, Frederick Olmsted insisted on a plate girder bridge; Richardson's contribution was ultimately the design of the decorative metalwork and lamps. The bridge was constructed in 1880–83. It was demolished around 1962 during construction of the Turnpike Extension and replaced by the Bowker Overpass, though the south abutment remains extant. Structures The Agassiz Road Duck House was designed by architect Alexander Longfellow, and built in 1897. It was used exclusively as a public restroom facility, and was closed after a damaging fire in 1986. The Duck House is sited within a prominent landscape