The city of Boston sought to condemn land in fee simple for use in constructing an entrance to an underground terminal for a subway. The owners of the land contend that no more than surface and subsurface easements are necessary for the terminal entrance and seek to retain air rights above thirty-six feet. The city argues that any building utilizing this airspace would require structural supports that would interfere with the city’s plan for the terminal. The city concedes that the properties around the condemned property could be assembled and structures could be designed to span over the condemned property, in which case the air rights would be quite valuable. Can the city condemn the property?