Maj. Jed. Hotchkiss, Confederate Military History, a library of Confederate States Military History: Volume 3, Virginia
Clement Anselm Evans, Ed.

Smarting under his failure to move on Richmond by way of Fredericksburg, Burnside was tempted, by a spell of mild weather, to try a movement toward Richmond around Lee's left, which he began by marching up the north bank of the Rappahannock, in January, 1863. But a storm set in, just after his movement began, which soon rendered the roads impassable and forced him to retire to his camps. He found the Confederates ready to dispute his crossing the Rappahannock at every point that he reached, and making fun of his attempts by erecting great signboards within their lines, visible to the Federal army, inscribed, ‘This way to Richmond.’ This movement is known in history as ‘Burnside's Mud Campaign.’