controlled minefields in ship channels. Fort Monroe was to be one of the largest installations of this program, and in 1896 construction began on new gun batteries there. The fort was the headquarters and main fort of the Coast Defenses of Chesapeake Bay, which was organized circa 1896 as an artillery district and redesignated in 1913. By 1906 the following batteries were completed: Battery Gatewood and the northeast bastion battery were built on the roof of the old fort's southeastern front and bastion; the parapet battery was on the roof of the eastern half of the old fort's southern side. The parapet battery had four emplacements, but only two of these had guns. Batteries Bomford and Barber were north of the old fort. Battery Humphreys was immediately northeast of the old fort and oriented southeast. Batteries Irwin and Parrott were in front of the old fort's southern side. The remaining batteries were on the isthmus extending north from the old fort in this order: Eustis, De Russy, Montgomery, Church, Anderson/Ruggles. Batteries Anderson and Ruggles were a line of four open-back mortar pits, originally with four mortars in each pit. Battery Anderson was the southern pair of pits and Battery Ruggles was the northern pair. Originally all four pits were named Anderson, but they were divided into two batteries in 1906. Battery Gatewood and the parapet battery were among a number of batteries begun after the outbreak of the Spanish–American War in 1898. Most of the Endicott batteries were years from completion, and most existing defenses still had muzzle-loading weapons. It was feared that the Spanish fleet might bombard U.S. east coast ports. Modern quick-firing guns were acquired from the United Kingdom and installed in new batteries. Battery Gatewood had four 4.72-inch/50 caliber guns while the parapet battery had four platforms for 8-inch M1888 guns with only two guns mounted. The northeast bastion battery was built to test an experimental 10-inch M1896 "depressing gun"; the battery was disarmed in 1908. Battery Humphreys was disarmed in 1910; batteries Barber, Gatewood, and the parapet battery were disarmed in 1913–1915. Fire control towers to direct the use of guns and mines were also built at the fort. During the Spanish–American War Fort Monroe also hosted the Camp Josiah Simpson Army General Hospital, including the post hospital and a tent camp on the old fort's parade ground. Twentieth century The Jamestown Exposition, held in 1907