Pat Monahan (right), lead singer for the group Train, and Jimmy Stafford, the group's guitarist, entertain a sold-out crowd at Wolf Trap Farm Park for the Performing Arts, in Vienna, Va., July 24. More than 100 servicemembers and their guests enjoyed the concert thanks to defense contractor Northrop Grumman and the USO of Metropolitan Washington. Photo by Samantha L. Quigley Pat Monahan (right), lead singer for the group Train, and Jimmy Stafford, the group's guitarist, entertain a sold-out crowd at Wolf Trap Farm Park for the Performing Arts, in Vienna, Va., July 24. More than 100 servicemembers and their guests enjoyed the concert thanks to defense contractor Northrop Grumman and the USO of Metropolitan Washington. Photo by Samantha L. Quigley SHARE: Download: Full Size (1.06 MB) Credit: VIRIN: 716663-I-BQC15-490.jpg Photo Gallery