<Tr> <Th> Daily traffic </Th> <Td> 43,000 </Td> </Tr> <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>

Where is the longest bridge in the united states located