Lee's plan was much the same as that of the Northern Virginia Campaign the year prior: turn the Union right flank by threatening Washington, D.C., using a forced march to the west around the Union line. To that end Lt. Gen. Richard Ewell's and Lt. Gen. A.P. Hill's corps were ordered to sweep around the Union right flank, Maj. Gen. Fitzhugh Lee, with three brigades of cavalry and infantry each, was to secure the Rapidan and prevent a Union advance into central Virginia, and Maj. Gen. J.E.B. Stuart was to lead the cavalry in advance of the infantry. The Confederate advance began on October 8 and was almost immediately detected by Union spies and the signaling station atop Cedar Mountain. Unsure of whether Lee was attempting to turn his right flank or make a retrograde movement toward Richmond, Meade ordered dispositions to counter either threat.