WADI CROSSING U.S. Marines patrol across the Musa Qal`eh Wadi crossing in Helmand Province, Afghanistan, Dec. 6, 2011. The Marines are assigned to the 2nd Battalion, 4th Marine Regiment. The structure was built by U.S. troops in an effort to bridge the Musa Qal`eh district center to neighboring villages during the rainy season when the wadi, or seasonal river, is full. SHARE IMAGE: Download Image: Full Size (0.07 MB) Photo By: VIRIN: 644395-U-ADJ82-308.jpg Photo Gallery