A memorial honoring 750 unknown Americans killed during the Mexican-American War stands at the Mexico City National Cemetery in Mexico City, Mexico, March 6, 2009. The cemetery, established in 1851 and closed in 1924, has 813 other veterans, members of their families and members of the U.S. Diplomatic Service interred on the grounds. A memorial honoring 750 unknown Americans killed during the Mexican-American War stands at the Mexico City National Cemetery in Mexico City, Mexico, March 6, 2009. The cemetery, established in 1851 and closed in 1924, has 813 other veterans, members of their families and members of the U.S. Diplomatic Service interred on the grounds. SHARE: Download: Full Size (3.77 MB) Tags: Photo Essays Credit: VIRIN: 301769-U-SHZ67-350.jpg Photo Gallery