Ahead of you is the surviving gate of the slaughterhouse district that fed a nation. The Union Stock Yards opened on Christmas Day 1865, consolidating the city's meatpacking into a single vast complex on the South Side. At its height it covered a square mile, employed tens of thousands, and processed more meat than anywhere on Earth, the engine behind Carl Sandburg's line naming Chicago Hog Butcher for the World.
It was also a place of brutal labor and squalor, exposed in Upton Sinclair's 1906 novel The Jungle, whose descriptions of filth so horrified readers that they helped force the first federal food-safety laws. The yards closed in 1971, and almost everything is gone. What remains is this limestone gateway, designed in the office of Burnham and Root, with a steer's head carved above the central arch.
Notice that stone bull above the arch: the last monument to the industry that built much of the city's fortune and its hardest history.