The Manassas Station Operations include the operations known as Bristoe Station, Kettle Run, Bull Run Bridge, or Union Mills.

It takes place August 25–27, 1862, in Prince William County, Virginia, as part of the Northern Virginia Campaign of the American Civil War.

On the evening of August 26, after passing around Union Maj. Gen. John Pope's right flank via Thoroughfare Gap, Confederate Maj. Gen. Thomas J. "Stonewall" Jackson's wing of the army strikes the Orange & Alexandria Railroad at Bristoe Station and before daybreak August 27 marches to capture and destroy the massive Union supply depot at Manassas Junction.

This surprise movement forces Pope's Army of Virginia into an abrupt retreat from his defensive line along the Rappahannock River.

On August 27, Jackson routs a Union brigade near Union Mills (Bull Run Bridge), inflicting several hundred casualties and mortally wounding Union Brig. Gen. George W. Taylor.

Maj. Gen. Richard S. Ewell's Confederate division fights a brisk rearguard action against Maj. Gen. Joseph Hooker's Union division at Kettle Run, resulting in about six hundred casualties.

Ewell holds back Union forces until dark.

That night, Jackson marches his divisions north to the Bull Run battlefield, where he takes position behind an unfinished railroad grade.