The grieving family of a former state park ranger has warned that no-one can take their safety for granted after it took nearly three weeks to find his body in the Yosemite wilderness.

Kirk Thomas Olsen, 61, was a seasoned backpacker and former staffer at Hearst San Simeon State Park in California.

But he disappeared during a four-day solo hike of Yosemite’s Ostrander Lake trailhead on August 27 after wandering away from the path.

More than 160 people have died in the park’s 1,187 square miles since 2007, many of them while traveling alone.

‘Take as many precautions you can because even with all the experience in the world, it doesn’t guarantee your safety sometimes,’ his niece Holly Leeson said.

Olsen had driven to the park from his home in San Luis Obispo for a five-day hiking trip on August 23.

He left a note on his car saying he expected to return to it on August 27 but the alarm was raised when he failed to appear.

He had set out to tackle the challenging Ostrander Lake hike which offers views of the granite domes topping Mount Starr King and the Clark Range.

Olsen was 6ft and 190 pounds, and an experienced backpacker.

But the 11-mile trail has a 1,500 feet climb and is described as ‘strenuous’ by the National Parks Service.

‘There is no drinking water available along this hike,’ it warns on its website. ‘Drinking water is available at Glacier Point seasonally, shortly after the road opens in spring until early fall.’

Days earlier hikers Ana Rodarte, 40, and Miguel Delgado, 63, had disappeared during what was expected to be a two-hour hike to Ostrander Lake.

But it took four dog search teams, 64 ground searchers, and an aircraft more than 48 hours to find them alive in the searing heat.

At the end of July the park claimed the life of Grace Rohloff, 20, who fell 200 feet down its notorious Half Dome after she lost her footing while descending cables on the cliff.

She and her dad Jonathan Rohloff were both experienced hikers but had slowed their descent to accommodate less experienced climbers and ended up getting stuck in a rain storm.

He immediately scrambled down after her, but was unable to get down the steep mountain to the spot where the University of Arizona student had come to rest.

It was an agonizing three hour wait until rescue teams could reach Grace, who had suffered a catastrophic head injury.

‘It was one of the most heartbreaking things I’ve ever seen,’ hiker Erin McGlynn said.

McGlynn, 20, was among the other hikers who encountered Rohloff as he was frantically praying for his daughter’s safety.

‘It was also one of the bravest things I’ve ever seen. He was able to compose himself, just in case he could provide any comfort to her. He did everything he possibly could have,’ she added.

Hundreds joined the search for Olsen as the alarm was raised and fears for his safety grew.

‘He’s a wonderful person and I found him very insightful and informative, extremely nice,’ said a former visitor to San Simeon where he worked as an interpreter and led elephant seal tours.

‘He is an experienced hiker and former park ranger himself and as a family we are struggling to understand what has happened to him out there,’ Leeson wrote on Facebook.

But his body was found on Saturday morning by investigators who believe he may have strayed from the path and become lost trying to find his way back.

‘I would like to say a genuine thank you to Yosemite National Park for their diligent efforts to find him, and to this community for the support,’ his niece wrote.

‘He was passionate not only about enjoying nature himself but educating others about the world and their surroundings,’ she added. ‘He really loved to share that kind of information with people.

‘Unfortunately Mother Nature in all of her glory does not account for past experience and solo hiking is never an endeavor that is without risks.

‘Please, whenever possible, travel with a companion and be safe.

‘The earth is beautiful and I myself will always be a supporter of our National Parks system and the opportunities they provide to see nature at her best, but take the necessary precautions and be safe in all of your endeavors.’