They were out to have a good time. It was a day trip with family and friends. A chance to create some memories.

Three young people from California—all in their twenties—were hiking in Yosemite National Park. They climbed up the steep and slippery Mist Trail until they reached Vernal Fall. It is one of Yosemite’s most popular and spectacular waterfalls.

It was a crystal clear, beautiful day.

There was a metal guardrail. It had been placed there by park authorities to keep visitors away from the swift-moving water of the Merced River. Just 25 feet from the precipice of the fall, the young people crossed over the guardrail and entered the water.