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18-486: Geiger Covered Bridge is a historic wooden covered bridge located at North Whitehall Township , Lehigh County, Pennsylvania . It is a 112-foot-long (34 m), Burr Truss bridge, constructed in 1860. It has vertical plank siding and an entry portal of stepped square planks. It crosses Jordan Creek . It was listed on the National Register of Historic Places in 1980. Covered bridge A covered bridge

36-736: A mile in length, but was destroyed by ice and flooding in 1832. The longest, historical covered bridges remaining in the United States are the Cornish–Windsor Bridge , spanning the Connecticut River between New Hampshire and Vermont, and Medora Bridge , spanning the East Fork of the White River in Indiana. Both lay some claim to the superlative depending upon how the length is measured. In

54-423: Is a timber- truss bridge with a roof, decking, and siding, which in most covered bridges create an almost complete enclosure. The purpose of the covering is to protect the wooden structural members from the weather. Uncovered wooden bridges typically have a lifespan of only 20 years because of the effects of rain and sun, but a covered bridge can last over 100 years. In the United States, only about 1 in 10 survived

72-419: Is approximately 1 mile (1.6 km) east of Medora and 9 miles (14 km) southwest of Brownstown . The Medora Covered Bridge was built in 1875 by J. J. Daniels at a cost of $ 18,142.00 and took nine months to build. The bridge was covered to protect the truss from the elements. Before the bridge was built people crossed the river by ferry. It has been reported but not verified that at one time there

90-651: The 1820s. Extant bridges from that decade include New York 's Hyde Hall Bridge and Pennsylvania 's Hassenplug Bridge , both built in 1825, and the Haverhill–Bath Covered Bridge and the Roberts Covered Bridge , in New Hampshire and Ohio respectively, both built in 1829. The longest covered bridge ever built was constructed in 1814 in Lancaster County , Pennsylvania, and spanned over

108-638: The 1950s, peaking at about 400 covered bridges. These mostly used the Howe, Town, and Burr trusses. Today, there are 58 covered bridges in New Brunswick , including the world's longest, the Hartland Bridge . Ontario has just one remaining covered bridge, the West Montrose Covered Bridge . Roofed, rather than covered bridges, have existed for centuries in southern Europe and Asia. In these cases,

126-450: The 20th century. The relatively small number of surviving bridges is due to deliberate replacement, neglect, and the high cost of restoration. Surviving covered bridges often attract touristic attention due to their rarity, quaint appearance, and bucolic settings. Many are considered historic and have been the subject of historic preservation campaigns. Typically, covered bridges are structures with longitudinal timber-trusses which form

144-518: The U.S., although it states that only 670 of those were standing when the 1959 edition was published. The tallest (35 feet high), built in 1892, is the Felton Covered Bridge , just north of Santa Cruz, California . Between 1969 and 2015, the number of surviving covered bridges in Canada declined from about 400 to under 200. In 1900, Quebec had an estimated 1,000 covered bridges. Relative to

162-457: The bridge's backbone. Some were built as railway bridges, using very heavy timbers and doubled up lattice work. In Canada and the U.S., numerous timber covered bridges were built in the late 1700s to the late 1800s, reminiscent of earlier designs in Germany and Switzerland . They tend to be in isolated places, making them vulnerable to vandalism and arson. The oldest surviving truss bridge in

180-620: The cover is to protect the users of the bridge rather than the structure. Examples include: In addition to being practical, covered bridges were popular venues for a variety of social activities and are an enduring cultural icon; for example: Medora Covered Bridge The Medora Covered Bridge is located in Carr Township in Jackson County , Indiana , and crosses the East Fork of the White River running parallel to State Road 235 . It

198-525: The mid-19th century, the use of cheaper wrought iron and cast iron led to metal rather than timber trusses. Metal structures did not need protection from the elements, so they no longer needed to be covered. The bridges also became obsolete because most were single-lane, had low width and height clearances, and could not support the heavy loads of modern traffic. As of 2004 , there were about 750 left, mostly in eastern and northern states. The 2021 World Guide to Covered Bridges lists 840 covered bridges in

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216-499: The most popular designs was the Burr Truss , patented in 1817, which used an arch to bear the load, while the trusses kept the bridge rigid. Other designs included the King , Queen , Lattice , and Howe trusses . Early trusses were designed with only a rough understanding of the engineering dynamics at work. In 1847, American engineer Squire Whipple published the first correct analysis of

234-611: The precise ways that a load is carried through the components of a truss, which enabled him to design stronger bridges with fewer materials. About 14,000 covered bridges have been built in the United States, mostly in the years 1825 to 1875. The first documented was the Permanent Bridge , completed in 1805 to span the Schuylkill River in Philadelphia . However, most other early examples of covered bridges do not appear until

252-567: The rest of North America, Quebec was late in building covered bridges, with the busiest decade for construction being the 1930s. Initially, the designs were varied, but around 1905, the design was standardised to the Town québécois , a variant on the lattice truss patented by Ithiel Town in 1820. The designer is unknown. About 500 of these were built in the first half of the 20th century. They were often built by local settlers using local materials, according to standard plans. The last agricultural colony

270-620: The world is the Kapellbrücke in Switzerland, first built in the 1300s. Modern-style timber truss bridges were pioneered in Switzerland in the mid-1700s. Germany has 70 surviving historic wooden covered bridges. Most bridges were built to cross streams, and the majority had just a single span . Virtually all contained a single lane. A few two-lane bridges were built, having a third, central truss. Many different truss designs were used. One of

288-684: Was founded in 1948, and the last bridge was built by the Ministry of Colonisation in 1958 in Lebel-sur-Quévillon . There are now 82 covered bridges in Quebec, Transports Québec including the Félix-Gabriel-Marchand Bridge , the province's longest covered bridge. In Quebec covered bridges were sometimes known as pont rouges (red bridges) because of their typical colour. Like Quebec, New Brunswick continued to build covered bridges into

306-412: Was opened in 1973. The covered bridge was closed to vehicular traffic at that time. In 2007, the bridge was added to the National Register of Historic Places . In June 2011 a rehabilitation of the bridge was completed. The original truss remained in place with a few repairs. The cedar shake shingles, siding (seven of the original boards, identified by square nail holes, were placed on the north side of

324-454: Was wooden railing down the middle of the bridge separating the two-way traffic. As the vehicles became wider, the railing was removed and it was then one-way. Until 1935 the bridge carried U.S. Route 50 when it (US 50) was moved four miles to the north. In 1968 the bridge was scheduled for demolition when the new modern parallel bridge was to be opened, but was saved by an order from then Governor Whitcomb in 1971. A modern parallel bridge

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