VIPER BASE U.S. soldiers establish a patrol base during Operation Viper Shake in the mountains surrounding Korengal Valley, Afghanistan, April 21, 2009. The troops are assigned to the1st Infantry Division's Company C, 1st Battalion, 26th Infantry Regiment. SHARE: Download: Full Size (0.08 MB) Credit: VIRIN: 138975-N-CHA24-580.jpg Photo Gallery