LOVELAND - Night was falling Monday as Elizabeth Weber drove along Highway 34 in Big Thompson Canyon. That's when she saw it - a man - coming out of the river nearby.

She called him a "wet man" in her Facebook post. After pulling over, she noticed a whole family on the other side of the river.

Victoria Sjolander admits she and her family was on the wrong side of the river, stuck, with her two little kids, her partner Korey Boyd and their two friends.

After a long and challenging hike, the six of them thought they were taking a shortcut down to the road.

They weren't. While they could see the road, they couldn't get to the road.

"And we thought, 'maybe this ravine,'" Boyd told 9NEWS. "It looked kind of like a trail but it was more of a rock slide, so we started following that down and got down to the river."

But it started getting darker and colder. The group began to worry.

"We got to the point where we needed to call 911," Sjolander said. "We need to get through - there's no other option."

As it happens so often on hikes, however, they didn't have cell service. There isn't any service in the whole of Big Thompson Canyon. So Korey's cousin swam across the river, running into Weber who'd been driving along, not expecting to see the wet man.

She drove down the road to get her husband, who is a firefighter, and the two of them found a house to call 911 from.

Sjolander said she and the others felt a sense of relief when they finally saw the rescuers from the Loveland Fire Rescue Authority.

Loveland Fire led the rescue while the Larimer County Dive Team and Estes Fire Protection District assisted.

The children, according to Korey, seemed like they were having a lot of fun. But the fun was over quickly, leaving this family with a memorable lesson.

"Yeah I'm definitely going to look at a topography map before I strike out again, and before I follow any trails online, I'll make sure it's an actual trail - not a rock climbing trail," said Boyd.