Why Is Fifth Avenue Known as MILLIONAIRES' ROW? A Look Through NYC's Gilded Age | IYKYK 

Before 5th Avenue was filled with world-renowned museums and high-end stores, it was actually home to Millionaires' Row, where ornate and extravagant Gilded Age mansions lined this expansive avenue. NBC New York’s Jennifer Vazquez explains it all on the series, IYKYK.