O2 (Millennium Dome)

Lonely Planet review

Since it closed at the end of 2000, having failed miserably in its bid to attract 12 million visitors, the huge circus tent-shaped O2 (renamed from the Millennium Dome in 2005) was, until recently for the most part unemployed. It has now hosted Bon Jovi and Barbara Streisand concerts and a massive exhibition called Tutankhamun and the Golden Age of the Pharaohs.

But that was little consolation (or cash) for developers Anschutz Entertainment Group, whose bid for it to house Britain's first regional supercasino had been rejected by the government that year. The future of the 380m-wide white elephant on Greenwich Peninsula that cost around £750 million to build (and more than around £5 million a year just to keep it erect) does look a lot brighter than it did, and it is now scheduled to host the 2009 World Gymnastics Championships and the artistic gymnastics and basketball events of the 2012 Olympic.

If you want to get a good view of what was the latest in tent technology at the turn of the millennium, you can see it from Docklands or Trinity Buoy Wharf or by taking a River Thames cruise to the Thames Flood Barrier.