The ROYAL FUSILIERS pursued the French army in the direction of _Pampeluna_, and when the enemy had effected his escape through the Pyrenean mountains, they were employed in the blockade of Pampeluna, a fortress of great strength, and provided with an efficient garrison. They were, however, soon relieved from this duty, and detached against a French division under General Clausel, which was at Logroño when the battle of Vittoria was fought; after a forced march of six days the FUSILIERS halted;--the enemy having effected his escape by the pass of Jaca. The regiment afterwards returned to the vicinity of Pampeluna, where it remained a few days, and subsequently penetrated the Pyrenean mountains; the fourth division taking post at Viscayret, in the valley of Urroz, and the ROYAL FUSILIERS being at Espinal, two miles in advance. Thus the British army, after years of toil and conflict, endured to procure liberty for the oppressed inhabitants of the Peninsula, had forced the intrusive monarch of Spain from his throne, and stood triumphant on the lofty pinnacles of the _Pyrenees_; but another mighty struggle was at hand, in which the innate valour and hardihood of the British soldiers were about to be tested. The French army had been re-organized by Marshal Soult, who pushed his divisions boldly forward to drive the British from the mountains. The enemy having made a demonstration of an attack on the front posts, two companies of the ROYAL FUSILIERS advanced on the 24th of July to a height westward of Roncesvalles, where they were joined by the remainder of the battalion during the night; on the following morning the enemy attacked Major-General Byng's post in Roncesvalles, and the fourth division was ordered to advance. A detachment of the twentieth regiment evinced signal gallantry in its attacks on the head of a French column; but was forced back by superior numbers. Some sharp fighting occurred during the day, and the ROYAL FUSILIERS had Lieutenant Knowles and six men killed; one serjeant and twenty-three rank and file wounded. The British maintained their positions during the day; but being opposed to very superior numbers, they withdrew after sunset: the FUSILIER BRIGADE being in the rear of the column, under Major-General Ross, the SEVENTH underwent a night of incessant toil and intense anxiety among the mountains. At day-light they fell in with posts of Major-General Byng's brigade, and the retrograde movement was continued, with short intermissions, until the allies gained a position in front of Pampeluna, where a determined stand was made.