The beginning of the war saw Grant still in Louisiana. In February 1861, Fannin, Grant &amp; Co sold out to the Southern Pacific, and Grant returned to Atlanta. After the Vicksburg Campaign, Confederate Chief of the Engineer Bureau Jeremy Gilmer contacted him to survey possible enemy crossings of the Chattahoochee River, and defensive works were begun in August, 1863. Grant explained that the fortification of Atlanta would be as difficult as that of Richmond, Virginia. Grant planned a series of 17 redoubts forming a circle over out from the center of town. It was bounded on the north on high ground (present location of the Fox Theatre), on the west by Ashby Street, on the south by McDonough Drive and on the east by Grant Park. Gilmer inspected the completed work in December 1863. Because of how the Battle of Atlanta unfolded, these fortifications were never really put to the test, the city's Mayor Calhoun capitulating to the siege after the railways to Macon were seized by Union forces and Confederate General John Bell Hood was forced to destroy his ammunition train after the Union victory at Jonesborough.