In 1827, the United States War Department decided to replace a 22-year old arsenal, Fort Belle Fontaine (located north of St. Louis on the bluffs above the Missouri River) with a larger facility to meet the needs of the rapidly growing military forces in the West. Lt. Martin Thomas selected a tract of land on a bluff overlooking the Mississippi River and procured the land for the new arsenal. It was close to the main military base, Jefferson Barracks, and had easy access to the city and the river. By 1840, 22 separate buildings had been erected, and a garrison of 30 ordnance soldiers manned the site, along with 30 civilian employees, who assembled finished weapons and artillery from parts supplied by private contractors and armories. In its original configuration it included Arsenal Island