Despite the plans for a surprise attack on Sevastopol being undermined by the delays, six days later on 19September, the army finally started to head south, with its fleets supporting them. The French were on the right of the allied line near the shore, with the Turks following them, and the British were on the left further inland. The march involved crossing five rivers: the Bulganak, the Alma, Kacha, Belbek, and Chernaya. By midday, the allied army reached the Bulganak and had its first sight of the Russians when a Cossack vanguard opened fire on the 13th Light Dragoons' scouting party. As the Light Brigade prepared to charge the Cossacks, Lord Raglan sent an order for it to retreat when a large Russian infantry force was discovered in a dip in the terrain ahead. The next morning, the Allied army marched down the valley to engage the Russians, whose forces were on the other side of the river, on the Alma heights.