Subscribe | UPI Odd Newsletter Subscribe Oct. 17 (UPI) -- The National WWI Museum and Memorial in Kansas City, Mo., opened a 100-year-old time capsule that contained items including newspapers and a letter from President Calvin Coolidge. The time capsule was buried inside the museum's Liberty Memorial Tower in 1924, with instructions left to open the container in 100 years. The time capsule commemorated the memorial's dedication. Advertisement The museum extracted the time capsule from the monument during the summer, a process that was complicated by 18 inches of limestone and concrete. Officials said the extraction was also made difficult by the presence of nitrate film in the container, which is known to be highly flammable. The time capsule's contents were revealed during a Wednesday ceremony. The objects included a copy of the U.S. Constitution, newspapers, a Bible and a copy of the U.S. declaration of war from April 1917. The box also contained letters, including one from President Calvin Coolidge and several from Allied commanders who attended the Liberty Memorial's 1921 groundbreaking ceremony. The time capsule also held a Nov. 1, 1921, printing plate from the Kansas City Star. The copper box bore multiple engraved signatures from people who officials were unable to identify, but they are believed to be members of the team who assembled the time capsule. Advertisement Read More Cyprus festival features 246-foot kebab Exotic caracal cat captured in Chicago suburb Minnesota farmer's 2,471-pound pumpkin wins world championship