The Panic of 1873 began in the United States after the Philadelphia and Reading Railroad failed in September 1873.
The railroad, commonly known as the Reading Railroad, had expanded aggressively and became unable to meet its obligations. Its failure followed the collapse of Jay Cooke and Company, a major financier of railroad construction, and helped intensify a nationwide banking and stock-market panic.
The New York Stock Exchange closed from September 20 to September 29, 1873, as confidence collapsed. Bank failures, business failures, falling railroad securities, and unemployment followed. The crisis was also connected to financial disturbances in Europe, particularly the Vienna crash earlier that year.
The event is sometimes described as the start of the Long Depression, though the timing and duration of that label vary by country and historian. The Reading Railroad's failure was an important trigger, not the only structural cause; excessive railroad building and fragile credit markets had created broader vulnerability.