Chicago – the birthplace of the skyscraper – is hosting its second architecture biennial this month. Here's a look at five of the tallest towers either approved or underway in the city.
Set to reach 1,186 feet at its highest point when it completes in 2020, local architect Jeanne Gang's Vista Tower will become the city's third tallest skyscraper and the tallest building in the world designed by a woman.
The residential skyscraper is currently under construction just south of the Chicago River. It comprises three blocks with undulating blue-green glass facades, which will rise to 46, 70 and 95 storeys.
Find out more about Vista Tower ›
American-German architect Helmut Jahn's tower for Chicago's South Loop is expected to top out at 832 feet (254 metres) and house 323 high-end residences.
Jahn's design includes curving facades, with glass portions broken up by opaque metallic bands marking each floor plate, and a top surrounded by metal mesh.
One Grant Park by Rafael Viñoly Architects
Proposed as a pair of skyscrapers, the One Grant Park scheme's first tower will climb to 829 feet (253 metres) at 113 East Roosevelt Road, in the South Loop neighbourhood. Its neighbour is slated to be built just to the west.
Rafael Viñoly Architects, responsible for New York's soaring 432 Park Avenue, designed the buildings as clusters of blocks that stagger upwards in height – similar to Chicago's current height record holder, the Willis Tower.
Find out more about One Grant Park ›
One Bennett Park by Robert AM Stern
New York-based Robert AM Stern designed this 70-storey skyscraper with predominantly stone facades, in contrast with the fully glazed towers on this list, as a nod to Chicago's architectural history.
The building will contain 350 residences and feature a park by landscape architecture firm Michael Van Valkenburgh at its base.
110 North Wacker by Goettsch Partners
To be built immediately beside the Chicago River, Goettsch Partners' design for this 800-foot (244-metre) office tower has been approved by the city, but is awaiting an anchor tenant before construction begins.
The skyscraper would sit over a portion of the riverwalk, balanced on giant three-pronged supports below a jagged facade.
The second Chicago Architecture Biennial runs 16 September 2017 to 7 January 2018.