Featured in this photograph are metropolitan New Orleans; the verdant terrain immediately outside the urban area showing river alluvium and levees; and the dark, rural landscape surrounding New Orleans with numerous lakes interspersed throughout the swampy wetlands that are prevalent in this part of the Mississippi River delta. Apparent are large Salvador Lake south of New Orleans; most of the 24-mile (39-kilometer) causeway that connects New Orleans with the north shore of Lake Pontchartrain; and the shorter causeway that connects the eastern end of New Orleans to Slidell on the north shore of the lake. The canal system along the east side of New Orleans is part of the Intracoastal Waterway. The meandering, sediment-laden Mississippi River illustrates why New Orleans is nicknamed the Crescent City.