A British climber crushed to death by falling rocks at Yosemite National Park had been been planning a dream adventure holiday with his wife.

Andrew Foster, 32, from Wales, was killed instantly when a 1,000-tonne slab of granite the size of a 13-storey building plunged from the face of the El Capitan monolith.

His wife Lucy, 28, was airlifted to hospital with critical injuries after the couple were caught in the rock fall during a three-week trip to the Californian park.

The pair had planned to leave their home in Wales after Christmas to travel around the Alps for 12 months.

Earlier this month Ms Foster posted on Facebook a picture of her smiling husband standing in front of a white van they had just bought for the trip.

She wrote: "We're moving out of our lovely house to live in a van for a year and travel around the Alps skiing, climbing and being X-treme to the max!"

Tributes had been paid to Mr Foster on the couple's shared Instagram account, on which they documented their travels.

The last photo on the account shows an exhausted but smiling Mr Foster in climbing gear, sat on a rock. It is captioned: "Yosemite has broken Andy. Time for a rest."

"So so sorry to hear the loss of Andrew. My heart is breaking for you and your family," one person wrote underneath.

Another comment read: "This is utterly heartbreaking. My thoughts are with your friends and family. Lucy I hope you make a full and speedy recovery."

Lucy and Andrew Foster were keen adventurers and went climbing most weekends (Instagram)

A spokesman for the park confirmed Mr Foster's identity and said his wife remained injured in hospital.

The couple, found with climbing equipment, are believed to have been scouting out the ascent from a trail when a "sheet" of granite around 130ft (40m) by 65ft (20m) plummeted from a height of 650ft (200m.)

Park spokesman Scott Gediman said: "With all the craziness I don't exactly know where they were going but chances are they were going up.

"From what I understand they were buried under rock... They were crushed by falling rocks."

He could not be specific about their injuries but said they were "consistent with tonnes of granite falling on [them]".

The couple, who met at Cardiff University, were both experienced climbers and skiers. Mr Foster proposed on a slope in the Alps in 2015 and they married the following year.

The couple wrote a blog about their "adventures in the mountains together", and published a detailed post about their preparations for climbing in Yosemite. The trip was reportedly planned as part of their wedding anniversary celebrations.

"Yosemite is an awesome place and for many climbers is one of the many places to go before you die," wrote Mr Foster. "Big walls often scare most UK climbers just due to the size but with the right attitude and a basic understanding of the skill then you’re in with a good chance of bashing out a route that you will remember for the rest of your life."

A cloud of dust is seen on El Capitanafter the rock fall that killed Andrew Foster (National Park Service)

Mr Foster, originally from Cheltenham, worked as sales rep for outdoor clothing and gear company Patagonia.

Alex Beasley, Patagonia’s country manager for UK and Ireland, said: “It is with much sadness that we mourn the loss of our dear friend and colleague Andrew Foster, who was killed in a tragic accident in Yosemite.

“He was a much-loved member of our team and a passionate climber, mountaineer and skier who loved being in the outdoors.

“Our thoughts and condolences are with his wife, Lucy, and their families. We offer them our deepest sympathies.”

The couple were the only known casualties of a series of rock collapses on Wednesday despite being with a group of other climbers.

The fallen rocks had a combined weight of about 1,300 tonnes, said park authorities.

One witness, Mike Kane, tweeted the largest collapse was "very loud", adding it was a "miracle more [were] not hurt".

A second rock fall at the site on Thursday led to one injured person being airlifted to hospital.

Mr Foster's death is the first fatality from a rock fall in the park in four years, according to the parks service. Before that the last fatality involving a climber in a similar accident was in 1999.