Chase Tower, located in the Chicago Loop area of Chicago, in the U.S. state of Illinois at 10 South Dearborn Street, is a 60-story skyscraper completed in 1969. At 850 feet (259 m) tall, it is the eleventh-tallest building in Chicago, the tallest building inside the Chicago 'L' Loop elevated tracks, and the 40th-tallest in the United States. Chase Bank has its U.S. and Canada commercial and retail banking headquarters here. The building is also the headquarters of Exelon. The building and its plaza (known as Exelon Plaza) occupy the entire block bounded by Clark, Dearborn, Madison, and Monroe streets.HistoryBefore the building was constructed, the Morrison Hotel, on its former site, was demolished in 1965. The building first opened in 1969 as First National Plaza. When constructed, it was the headquarters of First Chicago Corporation. In 1998, it became the headquarters for Bank One Corporation, and accordingly it was renamed Bank One Tower, The current name dates from October 24, 2005, after Bank One merged with Chase. Chase's retail bank division is based in the tower.