represented by Local 34, and service and maintenance workers are represented by Local 35, both of the same union affiliate UNITE HERE. Unlike similar institutions, Yale has consistently refused to recognize its graduate student union, Local 33 (another affiliate of UNITE HERE), citing claims that the union's elections were undemocratic and how graduate students are not employees; the move to not recognize the union has been criticized by the American Federation of Teachers. In addition, officers of the Yale University Police Department are represented by the Yale Police Benevolent Association, which affiliated in 2005 with the Connecticut Organization for Public Safety Employees. Yale security officers joined the International Union of Security, Police and Fire Professionals of America in late 2010, even though the Yale administration contested the election. In October 2014, after deliberation, Yale security decided to form a new union, the Yale University Security Officers Association, which has since represented the campus security officers. Yale has a history of difficult and prolonged labor negotiations, often culminating in strikes. There have been at least eight strikes since 1968, and The New York Times wrote that Yale has a reputation as having the worst record of labor tension of any university in the U.S. Moreover, Yale has been accused by the AFL–CIO of failing to treat workers with respect, as well as not renewing contracts with professors over involvement in campus labor issues. Yale has responded to strikes with claims over mediocre union participation and the benefits of their contracts. Campus Yale's central campus in downtown New Haven covers and comprises its main, historic campus and a medical campus adjacent to the Yale–New Haven Hospital. In western New Haven, the university holds of athletic facilities, including the Yale Golf Course. In 2008, Yale purchased the 17-building, former Bayer HealthCare complex in West Haven, Connecticut, the buildings of which are now used as laboratory and research space. Yale also owns seven forests in Connecticut, Vermont, and New Hampshire—the largest of which is the Yale-Myers Forest in Connecticut's Quiet Corner—and nature preserves including Horse Island. Yale is noted for its largely Collegiate Gothic campus as well as several iconic modern buildings commonly discussed in architectural history survey courses: Louis Kahn's Yale Art Gallery and Center for British Art, Eero Saarinen's Ingalls Rink and Ezra Stiles and Morse Colleges, and Paul Rudolph's Art & Architecture Building. Yale also owns and has restored many noteworthy