What major architectural feature does the Rookery Building have?

The Rookery Building is renowned for its stunning atrium, which showcases a unique glass and iron skylight. This major architectural feature is significant because it reflects the innovative design principles of the late 19th century, particularly the use of natural light in commercial buildings. The atrium not only enhances the interior environment of the building by allowing sunlight to flood the space, but it also serves as a central organizing element that connects various floors.

Designed by the architect Daniel Burnham, the Rookery Building is often considered a hallmark of the Chicago School of architecture, where functionality meets aesthetic beauty. The combination of glass and iron allows for a grandiose feeling of openness within the structure, showcasing the melding of art and engineering during that period. The atrium's design also emphasizes the building's historical significance, making it a landmark in Chicago's architectural landscape. This feature has been preserved and restored, contributing to the building's recognition and appeal to both tourists and architectural enthusiasts alike.