Christopher Johnson McCandless (/məˈkændlɪs/; February 12, 1968 – c. August 1992), also known by his pseudonym "Alexander Supertramp", was an American adventurer who sought an increasingly nomadic lifestyle as he grew up.

After graduating from Emory University in Georgia in 1990, McCandless traveled across North America and eventually hitchhiked to Alaska in April 1992. There, he entered the Alaskan bush with minimal supplies, hoping to live simply off the land. On the eastern bank of the Sushana River, McCandless found an abandoned bus, Fairbanks Bus 142, which he used as a makeshift shelter until his death. In September, his body, weighing only 67 pounds (30 kg), was found inside the bus by a hunter. McCandless's cause of death was officially ruled to be starvation, although the exact circumstances relating to his death remain the subject of some debate.

In the January 1993 Outside magazine, Jon Krakauer wrote an article about McCandless. Inspired by the details of McCandless's story, Krakauer published the biography Into the Wild, which was then adapted into a 2007 film directed by Sean Penn, with Emile Hirsch portraying McCandless. That same year, McCandless became the subject of Ron Lamothe's documentary The Call of the Wild.

Christopher Johnson McCandless was born in El Segundo, California. He was the elder child of Wilhelmina Marie "Billie" McCandless (née Johnson) and Walter "Walt" McCandless, and had a younger sister named Carine, born in July 1971. McCandless also had six half-siblings from Walt's first marriage, who lived with their mother in California and later in Denver, Colorado. In 1976, the family relocated to Annandale, Virginia, where McCandless's father was hired as an antenna specialist for the National Aeronautics and Space Administration (NASA). McCandless's mother worked as a secretary for Hughes Aircraft. The couple established a consulting business out of their home, specializing in Walt's area of expertise.

Carine McCandless alleged in her memoir The Wild Truth that her parents inflicted verbal and physical abuse upon each other and their children, often fueled by her father's alcoholism. She cited their abusive childhood, as well as his reading of Jack London's The Call of the Wild, as the motivating factors in her brother's desire to "disappear" into the wilderness. In a statement released to the media shortly before the memoir was released, Walt and Billie McCandless denied their daughter's accusations, stating that her book is "fictionalized writing [that] has absolutely nothing to do with our beloved son, Chris, his journey or his character. This whole unfortunate event in Chris's life 22 years ago is about Chris and his dreams."

In 1986, McCandless graduated from W.T. Woodson High School in Fairfax, Virginia. He excelled academically, although a number of teachers and fellow students observed that he "marched to the beat of a different drummer." McCandless also served as captain of the cross-country team, where he would urge teammates to treat running as a spiritual exercise in which they were "running against the forces of darkness ... all the evil in the world, all the hatred."

In the summer of 1986, McCandless travelled to Southern California and reconnected with relatives and friends. While he was there, McCandless learned that his father had lived for a time in a bigamous union with his mother who was his second wife; he had also fathered a child with his first wife after the birth of Chris and his sister by his second wife.

McCandless graduated from Emory University in May 1990 with a bachelor's degree in the double majors of history and anthropology. McCandless was an academic high achiever. After graduating, he donated his college savings of over $24,000 (approximately $59,000 in 2025) to Oxfam and adopted a vagabond lifestyle, working when necessary as a restaurant food preparer and farm-hand. An avid outdoorsman, McCandless completed several lengthy wilderness hiking trips and paddled a canoe down a portion of the Colorado River before hitchhiking to Alaska in April 1992.