Video: 'Minute By Minute' (5 videos)

(Friday, July 17, 1981, 7:05 p.m. CDT; during the Hyatt Regency walkway collapse) — 114 people were killed and 216 injured today when a pair of walkways above the lobby of the Hyatt Regency Hotel in Kansas City, Missouri, collapsed, one atop the other, during a tea dance.

Video: 'Mega Disasters - Hyatt Regency Skywalk Collapse'

This disaster contributed many lessons to the study of engineering ethics and errors, and to emergency management.

The event remains the deadliest non-deliberate structural failure in American history, and it was the deadliest structural collapse in the U.S. until the collapse of the World Trade Center towers 20 years later.