Which Chicago building is widely regarded as the world's first skyscraper?

The Home Insurance Building is widely regarded as the world's first skyscraper.

Designed by architect William Le Baron Jenney, the Chicago building was completed in 1885. Its innovative metal-frame construction carried much of the building's weight, allowing architects to use larger windows and build higher than traditional masonry methods permitted. It stood 10 stories tall and reached approximately 42 metres.

The building was later expanded to 12 stories in 1890 by Jenney. It was demolished in 1931 and replaced by the Field Building, now known as the LaSalle Bank Building. The Home Insurance Building's claim is about its structural innovation rather than absolute height.

Some earlier buildings, including New York's Equitable Life Assurance Building, were tall and used elevators, so definitions of “first skyscraper” can vary. The Home Insurance Building is the standard answer because its metal skeleton became a model for modern skyscraper construction.