K&L Gates Center is a skyscraper office building located in Downtown Pittsburgh, Pennsylvania. The building (long known as One Oliver Plaza and briefly as FreeMarkets Center and later Ariba Center) was completed in 1968. It has 39 floors, and rises 511 feet (156 meters) above downtown Pittsburgh. The building sits at the intersection of Liberty Avenue, Sixth Avenue and Wood Street. Facing the EQT Plaza tower across the street, it shares a city block with One PNC Plaza, Two PNC Plaza and Three PNC Plaza; this "superblock" was created by the closing of part of Oliver Avenue in the late 1960s. Located across the building is Wood Street Station, a subway station on Pittsburgh's light rail network.