Harry Alonzo Longabaugh (1867 - c. November 1908?), sometimes spelled Longbaugh, born in Mont Clare, Pennsylvania, also known as The Sundance Kid, was an outlaw and member of Butch Cassidy's Wild bunch, in the American Old West.
Although Longabaugh was reportedly fast with a gun and often referred to as a "gunfighter", Longabaugh is not known to have killed anyone prior to a later shootout in Bolivia, where he and Cassidy were alleged to have been killed. He became better known than another outlaw member of the gang dubbed "Kid", Kid Curry, who killed numerous men while with the gang. It is possible that often the "Sundance Kid" was mistaken for "Kid Curry", since many articles referred to the "Kid". The Sundance Kid did participate in a shootout with lawmen who trailed a gang led by George Curry to the Hole-in-the-Wall hideout and was thought to have wounded two lawmen in that shootout. With that exception, though, his verified involvement in shootouts is unknown.
Kid Curry and the Sundance Kid used a log cabin at what is now Old Trail Town in Cody, Wyoming, as a hide-out before they robbed a bank in Red Lodge, Montana. Butch Cassidy, the Sundance Kid, and other desperados met at another cabin brought to Old Trail Town from the Hole-in-the-Wall country in north central Wyoming. That cabin was built in 1883 by Alexander Ghent.
Historically, the gang was for a time best known for their lack of violence during the course of their robberies, relying heavily on intimidation and negotiation, but nevertheless if captured they would have faced hanging. However, that portrayal of the gang is less than accurate and mostly a result of Hollywood portrayals depicting them as usually "non-violent". In reality, several people were killed by members of the gang, including five law enforcement officers killed by Kid Curry alone. "Wanted dead or alive" posters were posted throughout the country, with as much as a $30,000 reward for information leading to their capture or death.
They began hiding out at a place they called the Hole In The Wall, located near Buffalo, Wyoming. From there they could strike and retreat, with little fear of capture, since it was posted high on a mountain top, with a view in all directions of the surrounding territory. Pinkerton detectives led by Charlie Siringo, however, hounded the gang for a couple of years.
Cassidy and Longabaugh, evidently wanting to allow things to calm down a bit and looking for fresher robbing grounds, left the United States on February 20, 1901. Longabaugh sailed with Butch Cassidy and Longabaugh's "wife", Etta Place, aboard the British ship Herminius for Buenos Aires in Argentina.
One theory is that both Butch and Sundance were later killed by soldiers in Bolivia in November 1908, after the two of them heisted a Bolivian mining company payroll. According to reports, the two were involved in a lengthy gun battle with the soldiers, who had surrounded them inside a building in San Vicente, ending with their alleged death.
However, there is some evidence to suggest that one or both returned to the United States, with Longabaugh dying in 1936. The subject remains a matter of dispute.