621 17th Street, Commercial skyscraper in Downtown Denver, United States

The 28-story building at 621 17th Street is a downtown commercial tower designed in a modernist style from the 1950s with a clean, geometric facade. This office building reaches approximately 385 feet high and contains commercial spaces that are integrated into Denver's central business district.

The structure was completed in 1957 and held the title of Denver's tallest building until 1968, when Brooks Towers surpassed its height. This shift reflected the city's rapid growth and changing skyline during the post-war development period.

The First of Denver logo on the building can be seen in the opening credits of the television series Dynasty. The two towers of the First of Denver Plaza, 621 and 633 17th Street, appear together in that sequence.

The tower is centrally located within Denver's business district and is easily accessible via the city's public transportation network. Visitors should note that this is an active office building, so access to certain areas may be limited.

This structure forms part of the First of Denver Plaza complex alongside the neighboring 633 17th Street tower built in 1974. The pairing of these two towers creates a unified building complex that shapes the appearance of the business district.