The ground chosen by Wellington to oppose Massena's advance was on the edge of the Sierra Busaco; which was separated, by a deep and narrow valley, from the series of hills across which the French were marching. There were four roads by which the French could advance. The one from Mortagao, which was narrow and little used, passed through Royalva. The other three led to the position occupied by the British force between the village of Busaco and Pena Cova. Trant's command was posted at Royalva. Terence with his regiment took post, with a Portuguese brigade of cavalry, on the heights above Santa Marcella, where the road leading south to Espinel forked; a branch leading from it across the Mondego, in the rear of the British position, to Coimbra. Here he could be aided, if necessary, by the guns at Pena Cova, on the opposite side of the river.

While the British were taking up their ground between Busaco and Pena Cova, Ney and Regnier arrived on the crest of the opposite hill. Had they attacked at once, as Ney wished, they might have succeeded; for the divisions of Spenser, Leith, and Hill had not yet arrived. But Massena was ten miles in the rear, and did not come up until next day, with Junot's corps; by which time the whole of the British army was ranged along the opposite heights.

Their force could be plainly made out from the French position, and so formidable were the heights that had to be scaled by an attacking force that Ney, impetuous and brave as he was, no longer advocated an attack. Massena, however, was bent upon fighting. He had every confidence in the valour of his troops, and was averse to retiring from Portugal, baffled, by the long and rugged road he had travelled; therefore dispositions were at once made for the attack. Ney and Regnier were to storm the British position, while Junot's corps was to be held in reserve.

At daybreak on the 29th the French descended the hill; Ney's troops, in three columns of attack, moving against a large convent towards the British left centre; while Regnier, in two columns, advanced against the centre. Regnier's men were the first engaged and, mounting the hill with great gallantry and resolution, pushed the skirmishers of Picton's division before them and, in spite of the grape fire of a battery of six guns, almost gained the summit of the hill--the leading battalions establishing themselves among the rocks there, while those behind wheeled to the right. Wellington, who was on the spot, swept the flank of this force with grape; and the 88th and a wing of the 45th charged down upon them furiously.

The French, exhausted by their efforts in climbing the hill, were unable to resist the onslaught; and the English and French, mixed up together, went down the hill; the French still resisting, but unable to check their opponents who, favoured by the steep descent, swept all before them.

In the meantime, the battalions that had gained the crest held their own against the rest of the third division and, had they been followed by the troops who had wheeled off towards their right, the British position would have been cut in two. General Leith, seeing the critical state of affairs had, as soon as he saw the third division pressed back, despatched a brigade to its assistance. It had to make a considerable detour round a ravine; but it now arrived and, attacking with fury, drove the French grenadiers from the rocks; and pursued them, with a continuous fire of musketry, until they were out of range. The rest of Leith's division soon arrived, and General Hill moved his division to the position before occupied by Leith. Thus, so formidable a force was concentrated at the point where Regnier made his effort that, having no reserves, he did not venture to renew the attack.

On their right the French had met with no better success. In front of the convent, but on lower ground, was a plateau; and on this Crawford posted the 43rd and 52nd Regiments of the line, in a slight dip, which concealed them from observation by the French. A quarter of a mile behind them, on the high ground close to the convent, was a regiment of German infantry. These were in full sight of the enemy. The other regiment of the light division was placed lower down the hill, and supported by the guns of a battery.

Two of Ney's columns advanced up the hill with great speed and gallantry; never pausing for a moment, although their ranks were swept by grape from the artillery, and a heavy musketry fire by the light troops. The latter were forced to fall back before the advance. The guns were withdrawn, and the French were within a few yards of the edge of the plateau, when Crawford launched the 43rd and 52nd Regiments against them.