don't know if its the same one but found this with a google search.
SUICIDE ROCK & THE RESERVOIR One of the foremost sights that met
the eye of the early travelers when they reached the mouth of Parley's
canyon before entering into the Valley of the Great Salt Lake, was a
huge mass of red rock which stood in the middle of the mouth of the
canyon. It consisted mainly of red sandstone and had stood as a
sentinel for centuries. For hundreds of years it stood as a watch tower
for the Indians until, as the story goes, an Indian maiden, upon
learning of the death of her brave, leaped from the top to her death on
the rocks below giving it the name of Suicide Rock. Now it is a
bill-board for the youth who dare climb its heights with a paint brush
or spray can
http://history.utah.gov/apps/markers/detailed_results.php?markerid=2660