In 1899 the regiment deployed to the Philippine Islands to help suppress a guerrilla movement in the Philippine-American War. The regiment returned to the Islands in 1905 and 1911. Though the 24th fought a number of battles in the Philippines, one of the most notable occurred on 7 December 1899, when nine soldiers from the regiment routed 100 guerrillas from their trenches.
How many years apart is the first time the regiment went to the Philippine Islands and the last time they returned?
12