Diane Marie O’Connell was 22 when she was killed on November 28, 1980, at Point Reyes National Seashore in Marin County, California. She had graduated from Cornell University. Diane and another hiker, Shauna May, were found raped, shot, and strangled on Mount Wittenberg.

Authorities later linked the murders to David Carpenter, known as the Trailside Killer, who attacked hikers on secluded trails in Marin and Santa Cruz counties over a 21-month period. Investigators say a surviving boyfriend of one of Carpenter’s last victims escaped and provided information that, together with testimony from a woman who had a prior encounter with Carpenter, contributed to his arrest. Carpenter was convicted in two separate trials for murders including Diane’s and was sentenced to death.

Anyone who knew Diane, saw her on the trails around Point Reyes in late 1980, or has information about that day is asked to come forward.