Chris McCandless had been carrying no identification when he died.  His remains, which were airlifted to Anchorage, were badly decomposed, and at the time of autopsy weighed only sixty-seven pounds (Chapter 2).

Alaska State Troopers were at a loss as to the identity of McCandless.  There were no clues in his journals, although they were able to obtain pictures of the young man as he looked when he was alive by developing the film in his camera.  When the story hit the newspapers, the Troopers were inundated by calls from people claiming to know whom he was.  One of those who called was Jim Gallien, who drove Chris into Alaska.  Gallien was able to identify Chris from his pictures.

McCandless had told Gallien that he was from South Dakota, so the search moved over there.  Wayne Westerberg was alerted by a friend who heard the news of a dead hiker found in Alaska on the radio.  Westerberg stepped forward, identified photos, and was able to supply a social security number from forms Chris filled out when he worked for him.  This discovery allowed authorities to direct their search to Virginia.

Walt and Billie McCandless had moved away to Maryland, but Chris's older half-brother Sam was still in Annandale.  Detectives tracked him down, and showed him the pictures from Chris's camera.  Sam was able to identify his brother, and the identification was finally made positive through dental records (Chapter 10).