Built 1897 (1897) NRHP Reference # 75000130 Opened 1897 Area 1,200 m² Bridge type Pratt truss bridge | Architectural style Pratt truss Address Franklin, NH 03235, USA Total length 71 m Number of spans 3 Added to NRHP 11 June 1975 | |
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Location Off US 3 over Winnipesaukee River, Franklin, New Hampshire Built by Boston & Maine Railroad Similar Contoocook Railroad Bridge, Bement Covered Bridge, Bog Bridge, Haverhill‑Bath Covered Bridge, Cornish–Windsor Covered Bridge | ||
The Sulphite Railroad Bridge, also known locally as the Upside-Down Covered Bridge is a historic railroad bridge in Franklin, New Hampshire. The bridge was built c. 1896-7 to carry the tracks of the Boston and Maine Railroad across the Winnipesaukee River between Franklin and Tilton. It is located about 0.7 miles (1.1 km) east of Franklin, and about 350 yards (320 m) south of US Route 3, and crosses the river at a point where its banks are quite steep; it is not readily visible from any roadway, but may be seen from the Winnipesaukee River Trail. The bridge is 234 feet (71 m) long, and consists of three spans, each supported by Pratt trusses resting on granite piers or abutments. The main central span measures 180 feet (55 m). The bridge is believed to be the only surviving "upside down" covered railroad bridge, in which the rail bed is laid on top of the bridge roof, whose purpose is to shelter the trusses below. The railroad line was shut down in 1973.
The bridge was listed on the National Register of Historic Places in 1975. The bridge is not in good condition, having been subjected to graffiti, vandalism, and arson, as well as the elements.