<Tr> <Th> Toll </Th> <Td> $5.00 (southbound) </Td> </Tr> <P> The Lake Pontchartrain Causeway, sometimes only the Causeway, is a fixed link composed of two parallel bridges crossing Lake Pontchartrain in southern Louisiana, United States . The longer of the two bridges is 23.83 miles (38.35 km) long . The southern terminus of the Causeway is in Metairie, Louisiana, a suburb of New Orleans . The northern terminus is at Mandeville, Louisiana . </P> <P> Since 1969, it was listed by Guinness World Records as the longest bridge over water in the world; in 2011 in response to the opening of the allegedly longer Jiaozhou Bay Bridge in China, Guinness World Records created two categories for bridges over water: continuous and aggregate lengths over water . Lake Pontchartrain Causeway then became the longest bridge over water (continuous) while Jiaozhou Bay Bridge the longest bridge over water (aggregate). </P> <P> The bridges are supported by 9,500 concrete pilings . The two bridges feature a bascule, which spans the navigation channel 8 miles (13 km) south of the north shore . </P>

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