The Secretary of the Interior is authorized to convey on behalf of the United States a certain tract of land, or any interest therein, being a portion of Independence National Historical Park project B, embracing fifteen thousand six hundred and fifty square feet, more or less, and situate on the northeast corner of South Fifth Street and Marshall Court (formerly Manning Street), city of Philadelphia, Pennsylvania, together with the improvements thereon, to the Redevelopment Authority of the City of Philadelphia in exchange for property, or interest therein, owned by the authority of approximately equal value and which the Secretary deems necessary for use in connection with the Independence National Historical Park. Property conveyed by the Secretary pursuant to this section shall thereupon cease to be a part of the park, and the property acquired in exchange therefor shall thereafter be a part of the park, subject to all the laws and regulations applicable to the park.