Expo 1893
Expo 1893, officially the World's Columbian Exposition, was a World Expo held in Chicago, Illinois. It was so iconic to the point where it was incorporated into Chicago's flag in the form of a star.
Chicago would host a World Expo again in 1933.
Ferris wheel
The original Ferris wheel was the centrepiece of the Midway Plaisance. After Expo, it was dismantled and then rebuilt at nearby Lincoln Park, before undergoing the same process just in time for Expo 1904 in St. Louis. It was ultimately demolished. Miraculously, the wheel's axle was discovered in 2007 near the site of its demolition.
They call them ferris wheels because they're made of iron.
Trains
John Bull
The then 62-year-old John Bull, built in 1831, was among the more notable locomotives on display. When the Smithsonian Institution ran it under its own power in 1981, it became the oldest operable steam locomotive in existence. As of 2025, we don't know what the oldest currently operating steam locomotive actually is.