Days into a hike along the Arroyo Seco river, a California family found themselves stranded at the top of a 40-foot waterfall.

Curtis Whitson, 44, his girlfriend Krystal Ramirez, 34, and his 13-year-old son Hunter Whitson were expecting to rappel down the side of the rock using the rope that Whitson found the last time he'd made the same journey, The Washington Post reported. But this time, the rope wasn't there.

"It was a sad realization, to know that our trip was over and we needed help,” Whitson told the Post. “Every inch down that river had committed us to a spot where we couldn’t get out."

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Whitson and his son tried to hike up and over the river, which was surrounded by rock up to 40 feet high on each side, CNN reported, but kept hitting dead ends. The group tried to yell for help and carve a message into a stick before Whitson had a stroke of genius.

He carved 'HELP' into the side of a lime green Nalgene water bottle and stuffed it with a note written on a piece of scratch paper Ramirez had brought to keep score when they played games, according to CNN. He tossed the bottle over the waterfall and the family retreated to a beach for the night where they used white rocks to spell out 'SOS' on a blue tarp.

They were awakened around midnight by a message from above: "This is search and rescue – you have been found! Stay put and we’ll be back to get you tomorrow morning.”

Whitson told the Post that two hikers found the message in a bottle and hiked to the campground to alert someone to call for help. A California Highway Patrol helicopter pilot told the newspaper that his crew used night vision goggles and infrared technology to find the family.

“A lot of pieces fell into place just right for these folks,” pilot Joe Kingman was quoted in the Post.

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