Libbie Prison in Richmond housed Union officers captured in the Civil War
Source: National Archives, Virginia, Richmond, Libby Prison (April 1865) and Libby prison, 1865
Major prisons for Union soldiers captured during the Civil War were located in Richmond (Libby Prison, Belle Isle, and Castle Thunder) and Danville.1
Confederates captured in Virginia were transported to prisons in Maryland, Delaware, and north of the Mason-Dixon Line
Source: Camp scene. Guarding Confederate prisoners (Shenandoah Valley, May, 1862)
Confederate prisoners were shipped north after capture by Union forces
Source: National Archives, Camp of Confederate prisoners at Belle Plain, Va., 1864
during the Civil War, many Union prisoners were sent to Andersonville, Georgia
Source: Library of Congress, A new batch at Andersonville (by William Waud, 1864-65)
military escorts conducted Civil War prisoners from capture sites on battlefields to prisons behind the front lines
Source: HathiTrust, Harper's Weekly, General Crawford Conducting Rebel Prisoners to His Rear (November 19, 1864, p.748)