Arlington House plays a unique role in American history. It was built between 1802 and 1818 by Washington's step grandson, George Washington Parke Custis, and his slaves on a hilltop overlooking the new capital city and the Potomac River. General Robert E. Lee later married into the family, and it became his family's plantation estate. After Lee resigned from the Union army and joined the Confederacy, Union troops captured the estate during the Civil War and made it their military headquarters to defend Washington from Virginia. After the war, the area became a community for emancipated slaves, and Union troops began burying their war dead on the grounds, in part to prevent Lee from returning. It eventually became Arlington National Cemetery, the burial site for many soldiers as well as President John F. Kennedy. As the most visited historic house in the national park system with some 650,000 visitors to the home, and nearly 2 million people to the grounds, the property has suffered much wear and tear. This project is restoring the home, slave quarters and grounds.