An 80-year-old Colorado man was convicted in the 1978 cold case murder in San Francisco of a teenage girl visiting the city from New York, authorities announced Thursday.

Mark Stanley Personette of Jefferson County was convicted of first-degree murder for the killing of 15-year-old Marissa Rolf Harvey, who disappeared on March 27, 1978, after going to San Francisco's Golden Gate Park for an afternoon of horseback riding.

Harvey, who was in the city from Queens to visit her sister for Easter, never returned to her sister's house. The next day, her body was found nearby in Sutro Heights Park by surfers walking through the area. She had been sexually assaulted and strangled, police said.

Marissa Rolf Harvey, 15, was slain in 1978 in San Francisco. Family photo via San Francisco Police De

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