REPORTER: An enthusiastic reception as London's mayor Boris Johnson officially opens Europe's tallest building to the public. At the very top, 800 feet up, is the observation deck. It's expected to attract thousands of visitors a year. And on a clear day it promises to offer spectacular views across the capital stretching as far as 40 miles.
BORIS JOHNSON, MAYOR OF LONDON: "I think it's a wonderful new attraction for London. What I love about it, is that it's not only sensational but there aren't any other buildings I know of where you can see all the bends in the river, it's like being in a plane."
REPORTER: But at 25 pounds a ticket it doesn't come cheap.
WOMAN: "I think it's well worth I, well worth it, good for tourism for London, yeah it is worth every penny."
MAN AND WOMAN: "It's amazing, just spectacular, a beautiful building and incredible view."
REPORTER: Below the viewing platform are 30 floors of office space, all still empty. So far the Shard's biggest tenant is the 5-star Shangri-La hotel. The restaurant space has also gone. But the ten penthouse apartments - tipped to cost up to 50 million pounds each remain unoccupied. Property experts say prices for exclusive properties in central London have risen more than 40 percent in the last three years. The Shard's height has already set records. The next challenge is filling it.
1 foot = 0.3048 m
1 mile = 1.60934 km