Thought to be designed by William Thornton, the architect of the U.S. Capitol, and long considered one of the most architecturally and historically significant properties in the city of Washington, Prospect House was built between 1787 and 1793 and sits high above the Potomac River at 3508 Prospect Street in Georgetown. This red brick Georgian-Federal house has been a show place for politicians and statesmen since Revolutionary War days, and is sited on nearly half an acre of beautifully manicured formal English gardens.  Among many renowned owners over the years, the property was the home of the first Secretary of Defense, James V. Forrestal, and during the Truman Administration Prospect House served as The White House Guest House for visiting dignitaries. Presidents Washington and Adams, the Marquis de Lafayette, the Shah of Iran, the President of France, and the poet Robert Frost have all been guests of Prospect House.