707 17th Street / Hilton Denver City Center (Denver, Colorado)

 hotel, office building, skyscraper

707 17th Street, formerly known as the MCI Building, is a skyscraper in Downtown Denver, Colorado. The building was completed in 1981 and rises 522 feet (159 meters) and 42 floors in height. It stood as the tallest building in Denver from its completion until it was surpassed by 1801 California Street in 1983. It has a floor area of 522,071 sq ft (48,502 sq m). It shares a basement, plaza, and loading dock with the adjacent Johns Manville Plaza. The building was designed by Metz, train, and Youngren and was developed by the Crescent Real Estate Equities Company.

The building was known as the MCI Plaza until 2005: MCI Inc. filed for bankruptcy in 2002, and the building was subsequently acquired by Verizon Communications on February 14, 2005. Prior to its bankruptcy, MCI occupied the uppermost commercial floors of the building and served as its primary tenant. However, even before MCI's acquirement, the building stood partially vacant and was nearing a 50% vacancy rate in 2002. This ended on September 30, 2002 when architectural, engineering, and construction management firm Carter & Burgess signed a deal to lease 86,000 square feet (8,000 sq m) of office space. This deal was one of the largest office transactions in Denver in 2006.

While the upper 22 floors of 707 17th Street contain office space, the lowest 20 floors of the building contain the Hilton Denver City Center, which contains 613 guest rooms and suites. It is the tallest mixed-use skyscraper in Denver.

707 17th Street features a somewhat unique setfront design, rather than the usual setback found in other Denver skyscrapers. The building bulges out and becomes wider above the 21st floor, and is thus given the term "setfront". The narrower region at the bottom of the building is home to the Hilton Hotel, whereas the upper, wider floors contain most of the commercial space. The building's facade is composed of black glass and is an example of international style black box architecture.