Tower Plaza is the tallest building in Ann Arbor, Michigan. It is located at 555 East William Street. The high-rise was constructed in 1969 and stands at 26 stories. The antenna stands at 292 feet tall and the roof is 267 feet tall. It was designed in the international style of architecture, primarily using concrete and glass. Originally a residential apartment building, it was converted to individually-owned condominiums in 1987.