The Battle of Lundy's Lane was a battle of the War of 1812 on July 25, 1814, fought in present-day Niagara Falls, Ontario. It was the bloodiest battle ever fought in Canada.

Lieutenant-General Gordon Drummond, with about 2200 British, Irish, Swiss mercenaries, Canadian and native troops, engaged an invading American army of approximately equal strength under General Winfield Scott, who had won the Battle of Chippawa on July 5.

The Americans emerged from a forest into an open field, and were easily picked off by the British artillery. Throughout the afternoon, the Americans eventually captured the cannons while they were being reloaded. The battle continued into the night, where darkness merged with smoke from the guns to heavily limit visibility. Both sides occasionally fired upon their own troops, as the battle moved towards a small hill near a cemetery.

Around midnight, the battle finally ended, with both sides having lost about the same number of men - 878 British and 860 American. Both General Scott and Jacob Brown, the two senior American commanders, were wounded. The next day, the Americans left the field, and burned the bridges behind them before meeting and defeating a small British force at Fort Erie, Ontario.

It was messy fighting in close quarters. Veteran British soldiers, who had fought against Napoleon in Spain and Portugal during the Peninsular War, were horrified at the carnage they had witnessed in Lundy's Lane. The battle confirmed that the American forces had evolved from a poorly-trained militia into a professional army.

Like the overall war, there is some dispute about the actual outcome of the battle. Canadians will say that the British held the field, and the Americans retreated; Americans will say the British retreated during the night, but took it back when the Americans retreated due to lack of supplies in the morning. In any case, it was the last attempt at an invasion of Canada by the Americans, and the war was essentially over after the battle, at least on the Canadian front.