How did Wellington use the ridge near Mont-Saint-Jean to defend his army at Waterloo?

At the Battle of Waterloo, Arthur Wellesley, 1st Duke of Wellington, utilized the terrain near Mont-Saint-Jean to create a formidable defensive position. His strategy relied on the following key elements:

• Reverse Slope Positioning: Wellington placed the majority of his troops on the reverse slope of the northern ridge. This effectively sheltered his infantry from direct French artillery fire.1
• Strategic Use of Cover: The first line of defense followed an unpaved road along the crest of the ridge, where thick hedges provided excellent natural cover for his men.1
• Advance Posts: To strengthen his line, Wellington fortified two critical advance posts located about 500 yards in front of his main position: the château and grounds at Hougoumont and the farm and sandpit at La Haye Sainte. These outposts acted as anchors that restricted the enemy's approach and forced French attacks into narrower zones of fire.1

By combining these topographical advantages with disciplined infantry tactics, such as forming defensive squares against cavalry, Wellington successfully held his position against repeated French assaults.1