The 16th Ohio, along with Col. DeCourcey's and Gen. Baird's brigades, made the incredibly difficult ascent up Roger's Gap on June 11 and down into Powell's Valley on the south side. Powell's Valley now offered a straight route to the northeast directly to the southern entrance to Cumberland Gap, still held by the Confederates. Since there was no significant attempt by the Confederates to engage the advancing Union forces, it is likely the enemy had no idea that the majority of Gen. George W. Morgan's forces had left Cumberland Ford, circled around and were now within striking distance of The Gap just 20 miles to the northeast with nothing in the way to stop them. Cpl. Wolbach:

On the 11th we descended, into Powell's Valley and established ourselves in the wood that skirted the base of the mountain. As the 9th Ohio Battery came down the steep and narrow road, one of their ten-pound Parrott guns, carriage and horses, took a frightful tumble down a dangerous incline. Horses and equipments were badly tangled up for a few minutes, but none of the poor animals were seriously hurt.

Some considered DeCourcey's movement up and over Roger's Gap one of the most brilliant achievements of the war - crossing two brigades with thirty pieces of cannon over such a difficult pass. The feat was later described by Cpl. Theodore Wolbach, Company E:

The task of getting the artillery to the top of the mountain was one of immense toil, as many men now living are ready to testify. ...On the 11th we descended, into Powell's Valley and established ourselves in the wood that skirted the base of the mountain.

Pvt. Peter Perrine, Company C, states:

Camped in a grove on rolling ground in Powel valley [Powell's Valley]. had splendid spring water. remained here until the 18th.

Pvt. F. H. Mason, Company A of the 42nd Ohio, brigaded with the 16th Ohio, gives us his perspective:

The ascent was two miles in length, with a sheer altitude of a thousand feet. Twelve horses were attached to each gun or caisson and in places even this was insufficient. Prolonges were spliced and manned by regiments, and the guns dragged by main force up declivities which the horses could hardly climb. In other places the road had to be cleared and graded anew, but the pluck and zeal of the men were superior to all difficulties and before evening of the second day (June 12) DeCourcey's brigade, with the Ninth Ohio Battery, had crossed the mountain into Powell's Valley.