Lake Pontchartrain Causeway is one of the most famous beam bridges in the world. It is the longest continuous over-water bridge on Earth. "The Causeway," as it is often referred to, is 23.83 miles in length.
The Lake Pontchartrain Causeway crosses Lake Pontchartrain in Southern Louisiana in the United States. It cuts through the lake from Mandeville in the north to Metairie, a suburb of New Orleans, in the South. The bridge actually consists of two bridges in parallel, each going one way. The first was opened in 1956 and the second in 1969. The construction of the bridge reduced driving times by over 50 minutes when it was first opened, boosting commerce on both ends.