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The Southwestern Bell Building is a 28-story, 121.0m skyscraper constructed to be the headquarters of Southwestern Bell Telephone in downtown St. Louis, Missouri. At the time of its construction it was Missouri's tallest building.The building, which was one of the first in St. Louis to use setbacks, has 17 individual roofs.Its architect was Mauran, Russell & Crowell, who also designed the Federal Reserve Bank of St Louis and the Railway Exchange Building (St. Louis). I.R. Timlin, Southwestern Bell's company architect, was associate architect on the project.

The Missouri Athletic Club Building, also known as the Missouri Athletic Association Building, is a historic building having Renaissance Revival architecture. It was listed on the National Register of Historic Places in 2007.The building is the headquarters of the Missouri Athletic Club. It is located at 405 Washington Avenue, at the corner of Fourth Street, adjacent to the entrance to the Eads Bridge on the Missouri side. The thirteen-story clubhouse designed by William B. Ittner contains four restaurants, a cigar parlor, a ballroom, a barber shop, numerous private meeting rooms, a reading room, a billiard parlor, a rooftop deck, 80 guest rooms, and full-service athletic facilities. The athletic facilities include weight training, a golf practice room, a pro shop, whirlpools, tanning beds, wet and dry saunas, trainers, pros, a masseuse, squash courts, racquetball courts, and handball courts.