Sept - Oct 1781, The Battle of Yorktown, also known as the Siege of Yorktown. General George Washington's defeat of Lord Cornwallis's British army, causing the British to surrender and ending the American Revolutionary War. The British were being defeated by the American colonists, causing the British government to negotiate an end to the American Revolution, giving colonists their freedom.
The Maryland State House - America's First Peacetime Capitol and the oldest state house still in legislative use. It was completed in 1779 and was the site of nationally important events during the American Revolution, including George Washington's resignation as commander in chief of the Continental Army from the army, and the ratfication of the Treaty of Paris - and so goes the name of a very fine restaurant in Annapolis :)