U.S. Navy Adm. Mike Mullen, chairman of the Joint Chiefs of Staff, and German Gen. Volker Wieker, chief of staff of the German Armed Forces, take a boat tour of Berlin on the Spree River, June 9, 2011. Mullen is on a seven-day trip visiting Egypt and Europe to meet with counterparts and leaders. U.S. Navy Adm. Mike Mullen, chairman of the Joint Chiefs of Staff, and German Gen. Volker Wieker, chief of staff of the German Armed Forces, take a boat tour of Berlin on the Spree River, June 9, 2011. Mullen is on a seven-day trip visiting Egypt and Europe to meet with counterparts and leaders. SHARE: Download: Full Size (9.94 MB) Tags: Photo Essays Credit: VIRIN: 081119-R-JMU72-128.jpg Photo Gallery