The Spacecraft Magnetic Test Facility at the Goddard Space Flight Center in Greenbelt, Maryland, United States, was built in 1966 to allow the evaluation of magnetic movement in spacecraft. The building is constructed on non-magnetic materials and contains a magnetic coil system that allows the cancellation of the Earth's magnetic field. This unique building was designated a National Historic Landmark in 1985. The facility is used to determine and minimize the magnetic movement of unmanned spacecraft and to calibrate flight magnetometers.