Next stop - New Orleans! Just after leaving the Slidell, Louisiana station, Amtrak Train 19 (Crescent) crosses Lake Pontchartrain on the evening of Thursday, July 16, 2020. This is the longest railroad bridge in the United States at 5.8 miles. The adjoining US Route 11 road bridge has been closed for construction for over a year, its lift section otherwise normally found in the lowered position.