Architects: D.H. Burnham & Co.

The Flatiron in History: Reaction to Chicago architect Daniel Burnham's building was critically mixed at the time, but eventually the terra cotta structure that resembled an iron became a visual touchstone for both the city and the neighborhood named after it.

The Flatiron Today: After its exterior was restored in 1991, the Flatiron Building presided over the digital boom that for a time made "Silicon Alley" the more common name for its domain.

Trivia Tidbits: It's the oldest remaining skyscraper in New York... When first built, people feared it would fall over... And, the term "23-skidoo" was coined after the building: on windy days, men would stand near the building (which seemed windier than other places) to try and catch women's skirts blowing up. Police officers would round 23rd street to chase them away.

Address: 175 Fifth Avenue on 23rd Street at the intersection of Broadway and 5th Avenue
• Unofficial Website and Unofficial Website 2