The Pan-American Exposition was held in Buffalo, New York from May 1 to November 2, 1901. Buffalo was chosen as the location because of its size (at the time it was the eighth largest city in the U.S. with a population of approximately 350,000) and also because of its well suited railway connections. The grounds spread across 342 acres and were located between Delaware Park Lake to the south, the New York Central railroad track to the north, Delaware Avenue to the east, and Elmwood Avenue to the west.

The Exposition included educational exhibits as well as a Midway. The educational exhibits showcased the latest advancements in technology, most notably electricity. A major feature was electric lighting which utilized hydroelectric power generated in nearby Niagara Falls. Many of the Exposition buildings, including the prominent Electric Tower, were covered in light-bulbs creating a beautiful and unprecedented sight. The Pan-American Exposition also hosted some of the top engine manufacturers of the time. These companies provided "working exhibits" that actually functioned in the day-to-day operation of the Exposition. The Midway at the Pan-American Exposition provided visitors with entertainment and consisted of more than 42 exhibits. Some of the main attractions of the Midway included the "House Upside Down," "Cleopatra's Temple", and the "Foreign Villages."

The Pan-American Exposition is most widely known as the location of President McKinley's assassination. On September 6, 1901, while in a receiving line at the Exposition's Temple of Music, President McKinley was shot twice by anarchist, Leon Czolgosz. McKinley was taken to the Exposition's hospital where he was operated on by a number of prominent Buffalo surgeons including Roswell Park. The President was then taken to the home of John Milburn, head of the Exposition's Board of Directors, to recover. After his condition appeared to improve, McKinley eventually died on September 14 in the Milburn home due to infection and gangrene from the gun shot wounds.