The Dey Mansion Washington’s Headquarters is a historic house museum, curated to provide visitors with the experience of stepping back in time. Dey Mansion guests are transported back to the Colonial Era as they walk through the front door of the home of Colonel Theunis Dey. The mansion served as General George Washington’s headquarters during the summer and fall of 1780, and played a significant role in the American Revolution. Today, the Dey Mansion staff hosts tours, lectures, and special programs – showcasing life in Colonial America, the events and people of the American Revolution, and the value and need for historic preservation.