London's Shard skyscraper observation deck opens to public
The observation deck on the Shard - western Europe's tallest building - has opened to the public.
London Mayor Boris Johnson cut a ribbon to the viewing platform, which is positioned 243m (800ft) up the skyscraper.
He was joined by its architect Renzo Piano for the opening of the attraction, The View from The Shard.
The Shard, which stands next to London Bridge station, is 310m (1,016ft) - 87 storeys - tall.
Mr Piano said: "This building is magic for a number of reasons.
"First, because it's in London, second, because it's so tall, and third, because this building is a part of London. It's a sense of London."
There was a sense of celebration as one couple from Epping Forest, Essex, got engaged on the observation deck.
James Episcopou, 22, got down on one knee to propose to his girlfriend Laura Taylor, 22.
On a clear day, visitors are promised a spectacular 40-mile panoramic view of the capital.
But wet and cloudy weather meant visibility was restricted for the 4,800 people who have already paid for admission on Friday.
Ticket prices are £24.95 for adults and £18.95 for children.
According to The View from the Shard website, there will be no refunds.
Instead, visitors will be able to return at another time if the bad weather fails to clear.
Mr Johnson described the building as "a most amazing place".
He said: "It's the closest thing to being in an airplane and looking down on London."
Visitors to the attraction - on floors 68, 69 and 72 - will be whisked up in two high-speed lifts within around 60 seconds.
They will be able to look through special telescopes known as Tell: scopes.
These show not only a live "as it is" image but, at the push of a button will show what a clear-day view would be as well as a sunset view and a night view.
The Shard is part of a £2bn redevelopment of the London Bridge area.
The triangular-shaped building has 600,000sq ft of offices, three floors of restaurants and a 200-room Shangri-La hotel which is due to open this summer.
There are also 10 luxury apartments which are expected to be priced as high as £50m each.
Irvine Sellar, chairman of Sellar Property and developer of the Shard, said: "I think Londoners will feel ownership of the Shard. They'll adopt it as the Parisians adopted the Eiffel Tower or the Americans adopted the Empire State."