Thrillseekers took flight over London’s skies on Friday as a 52 metre-high zip wire opened above the River Thames.

The line, which was 1,480ft (450m) long, was installed by the London Fire Brigade for one day only, raising over £1 million for Evelina Children’s hospital.

Twenty fundraisers, who pledged to donate £50,000 or more to take part, were catapulted across the river at 40 miles an hour between St Thomas's Hospital North Wing and Victoria Tower Gardens.

Experts and firefighters worked through the night to install the ride that used 500 metres of specially manufactured rope with the strength of steel cable, capable of withstanding a load of 12 tonnes.

The stunt was conceived by deputy assistant commissioner Andy Roe, whose nine-year-old son Zaki was treated at Evelina London Children’s Hospital.

“My son might not be alive today if it weren’t for the NHS and in particular Evelina Children’s Hospital and so I wanted to find a way to thank the remarkable staff at this fantastic hospital.

During the many hours I spent by my son’s bedside, I realised that I could use my specialist skills to rig up a zip wire from the roof of the hospital across the Thames and that perhaps people would pay for the chance to speed across it like a firefighter,” he said.

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“I’ve got to warn you, this is not a trip for the faint hearted, it will feel like you are flying directly into the Houses of Parliament.

There is no other white knuckle ride like it in the world. It’s great that I have a chance to showcase the Brigade’s skills and raise money as part of celebrations for London Fire Brigade’s 150th anniversary.

In my view there’s no better way to support one of the leading children’s hospitals in the country in helping them to continue their vital work.”

Other participants included British model Rosie Tapner, The Only Way is Essex star Fearne McCann, and Lord Stanley Fink, Evelina London’s President, who is on track to raise £100,000 for taking part.

The money will go towards the £2.7 million needed to build a dedicated clinical research facility at the hospital, allowing vital research into treatments and cures for conditions including autism, epilepsy, congenital heart disease, kidney disease and allergies.