 The Tower Building of the Little Rock Arsenal , also known as U.S. Arsenal Building , is a building located in MacArthur Park in downtown Little Rock , Arkansas . Built in 1840 , it was part of Little Rock 's first military installation . Since its decommissioning , The Tower Building has housed two museums . It was home to the Arkansas Museum of Natural History and Antiquities from 1942 to 1997 and the MacArthur Museum of Arkansas Military History since 2001 . It has also been the headquarters of the Little Rock Æsthetic Club since 1894 . 
