The Auditorium Building is the oldest remaining skyscraper in Chicago. It was designed by Dankmar Adler and Louis Sullivan, and construction of the building was completed in 1890. The Auditorium was unique for its time for having massive load bearing outer walls and the interior contained a 4,300 seat auditorium. Working under Sullivan, Frank Lloyd Wright assisted in the designs of some of the interior spaces of the Auditorium. Model by Austin Metzger.