The yellow dot marks the location of the Apollo 15 landing site near Hadley rille. The landing occurred on a dark mare plain called Palus Putredinis or Marsh of Decay. Hadley rille is a sinuous channel about 1300 feet (400 m) deep and about 4300 feet (1300 m) wide near the landing site. The Hadley C crater next to the rille is about 3 miles (5km) in diameter. The prominent mountain to the upper right of the landing site is Mt. Hadley. The Apennine mountains, to the right, form part of the southwest rim of the huge Imbrium impact basin and stand up to 2 miles (3km) above the surface. Sunken rilles (graben) lie parallel to this impact basin rim. The large Apennine mountain closest to the landing site is Hadley Delta. The 6 mile (10km) diameter crater Aratus is visible in the lower right. Apollo 15 was the first mission in which astronauts drove a lunar rover. Three surface excursions were made totaling 18.5 hours of manned exploration. (Apollo 15 Metric camera stereo photo AS-15-M3-586 & 587, orbit 22)