The Washington Monument construction began with the laying of the cornerstone on July 4, 1848. The construction occurred in two main phases: the first from 1848 to 1854, and the second from 1879 to 1884. The initial construction stopped in 1854 due to funding shortages and other difficulties, including the American Civil War. Construction resumed in 1879 under the U.S. Army Corps of Engineers, with Lieutenant Colonel Thomas Lincoln Casey overseeing the project. The monument was completed with the setting of the capstone on December 6, 1884. After dedication in February 1885, it officially opened to the public on October 9, 1888.