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Yale's central campus in downtown New Haven covers 260 acres (1.1 km2) and comprises its main, historic campus and a medical campus adjacent to the Yale-New Haven Hospital. In western New Haven, the university holds 500 acres (2.0 km2) of athletic facilities, including the Yale Golf Course. In 2008, Yale purchased the 136-acre (0.55 km2) former Bayer Pharmaceutical campus 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 7,840-acre (31.7 km2) Yale-Myers Forest in Connecticut's Quiet Corner—and nature preserves including Horse Island.

What campus did Yale buy in 2009?
unanswerable