On July 7, 1861, the 79th New York Infantry moved to Virginia as Major General Irvin McDowell began the advance of the Union Army that would lead to the First Battle of Bull Run. The regiment was in the division of Brigadier General Daniel Tyler and the brigade of Colonel William T. Sherman. On July 18, 1861, Tyler's division and the 79th New York Infantry participated in a reconnaissance in force in which the regiment came under fire and where the Union force was unable to penetrate the Confederate line at the Battle of Blackburn's Ford.