As the Union army moved up the east side of the Blue Ridge Mountains on the 29th and 30th of June, 1863 the 1st Corps, under General John Reynolds, was in the van and headed toward Emmitsburg. To enhance the coordination and effectiveness of his "left wing" George Meade had given Gen. Reynolds the authority to direct the movements and positioning of the 3rd and 11th Corps as well. By the 30th all 3 Corps had been sent to Emmitsburg, within marching distance of Gettysburg.
 

To the west, screening these moves and feeling for Lee's Army of Northern Virginia, was the cavalry division of Brig. General John Buford. Commanding some 4600 troopers, Buford had crossed South Mountain into the Cumberland Valley on the 29th. He then moved northward searching for rebel activity and late on that same day his division re-crossed South Mountain. Near the town of Fairfield one of his brigades skirmished with rebel units. Avoiding a larger battle, Buford withdrew southward to Emmitsburg where on the morning of the 30th he reported the presence of the Confederate infantry he had discovered. Buford then took two of his brigades, those under Col. William Gamble and Col. Thomas Devin, 12 miles to the north to the town of Gettysburg. His remaining brigade he had left near Fairfield with a watchful eye on the enemy there and on any effort to turn Meade's left.
 

By 11 AM the Union troopers arrived in Gettysburg, which had 2400 residents. Their entry proved to be quite timely. Not only did they capture several enemy soldiers, probably stragglers from Ewell's divisions, but also arrived just as a large Confederate force was approaching from the west. Moving down the Cashtown (Chambersburg) Road was the brigade of Gen. James J. Pettigrew. Pettigrew's soldiers, part of Gen. Henry Heth's division of A.P. Hill's Corps, were intending to search Gettysburg for supplies--- especially shoes, which were badly needed by the footsore and sometimes barefoot Southern soldiers. Unsure of the force now in front of him and under orders to avoid a general engagement Pettigrew retired back to the west.
 

John Buford would later claim he had "pushed" the North Carolinians back up the road but there was little if any exchange of gunfire.
 

As the rebels "retreated" toward Cashtown Buford had assigned Gamble's brigade, about 1600 men, to secure that route and then delay the Confederate advance he suspected would come. He then sent word to Meade and Reynolds that he would attempt to hold his position until the infantry could arrive.
Pettigrew, meanwhile, had bivouacked his weary men 4 miles from town, near Marsh Creek. After setting up a picket line he then rode on to Cashtown to report the blue-clad troopers to Henry Heth. It was now late afternoon on the 30th.
 

As Pettigrew was delivering this information to Heth, A.P. Hill arrived and personally heard of the reported cavalry. James Pettigrew had made a pre-war mark for himself as an author, diplomat, and lawyer and was regarded as a top-flight officer. Despite these strong credentials both Hill and Heth doubted whether there was a strong presence of the Army of the Potomac in or around Gettysburg as Pettigrew had reported. Their intelligence still placed Meade near Pipe Creek, 20 miles distant. Both Generals felt that the cavalry that Pettigrew had seen must be only a small body detached for observation.
Under such a belief Henry Heth turned to Hill and asked if he had any objection to Heth taking his division to Gettysburg the next morning to "get those shoes?" Hill, aware of Lee's order to not bring on a general engagement until all 3 of the ANV Corps were up, responded that he had "none in the world." (Heth's claim that his intent was just to "get those shoes" has been questioned. This line of inquiry asks why would he need bring an entire division for such a simple task? Especially if faced by a mere detached observation force? The nature of this forceful reconnaissance is less than surprising, however. Heth was known for his impetuous nature in combat and Hill, as a rule, pitched into whatever was to his front.)

Just west of Gettysburg the most outstanding features of the Pennsylvania countryside are three long, low ridges running north and south. Three-quarters of a mile from Gettysburg is Seminary Ridge, named for the Lutheran Seminary which sat near it's crest. One-half of a mile further west is McPherson's Ridge. On it's slopes was a wooded lot known as McPherson's Wood. Another half mile on, past the shallow Willoughby Run, was Herr Ridge. The Cashtown Road, Henry Heth's route of advance crossed all three. It was along these rises and the nearby depressions that the Battle of Gettysburg would begin.
At 5:00 AM on the 1st of July, Henry Heth's division, with James Archer's Brigade in the lead, set off from their Marsh Creek bivouac. Informed of this move by Gamble's most forward positions Buford sent word to Reynolds to hurry his infantry. After sounding this alert Union pickets served to slow the rebel advance as they forced Archer's infantry to deploy into battle line on both sides of the Cashtown Road. Then with gradually increasing pressure the men in gray shoved back or aside Gamble's pickets.
Around 8:00 Buford ordered Gamble's entire brigade to form along Herr Ridge and to straddle the road. Faced with a more determined defense Heth then committed a second brigade, that of Gen. Joseph R. Davis (nephew of the Confederate President). Despite a rapid fire laid down by the Union troopers, using there breech-loading carbines to good effect, the more numerous rebels still came on and soon swept Gamble off the ridge and across Willoughby Run.
 

As Gamble's Brigade fell back to McPherson's Ridge Buford, observing from the cupola of the seminary, committed Devin's Brigade to their right. These 1000 men extended the Union line to well north of town. Soon the entire length was threatened.
 

It was near 9:30, with Buford fearing his line would crumble under the weight of the Heth's advance, that John Reynolds arrived on the scene. Reynolds found the agitated Buford at the seminary, and asked, "What is the matter John?" Buford responded, "The devils to pay!"
 

With the 1st Corps rapidly approaching along the Emmitsburg Road the two generals quickly discussed the deteriorating situation. Buford said he thought he could hang on for a short while only. Reynolds, after hurrying a message to Meade reporting the advance of a strong Confederate force, then rushed back to the Emmitsburg road to await and then direct the approaching infantry.
 

Setting the pace was the 1st Division under Brig. General James Wadsworth. Reynolds led them himself over Seminary Ridge and up McPherson's. There he personally placed a 6-gun battery near the Cashtown Road and the lead regiments to it's left and right. They barely had time to deploy when rebel soldiers appeared, within range, to their front.
 

It was now about 10:30 and the first Union crisis of the battle had been averted. John Buford's cavalry had slowed the Confederate advance just enough. John Reynolds and the infantry now stood between Hill and the town while tens of thousands of men hurried to a usually sleepy Gettysburg.