London - Ten months before it hosts the Olympics, London is battling against the odds to upgrade its transport system to carry the millions of expected visitors around the city for the Games.
The eye-watering size of the transport budget for the Olympics speaks volumes about the size of the task - it is £6.5bn, compared with a budget for the Games of around £9.3bn, not including transport.
With its creaking underground train system and roads which even a congestion charge has done little to relieve, London was always facing an uphill task to be ready to transport the eight million visitors expected next July and August.
Graham Stephens, the coordination manager for the Olympics for the state-owned Transport for London (TfL) body, said transport was earmarked from the off as a potential problem.
"The first advisors for the London bid helped us a lot when they stressed right at the beginning of the process that transportation was a major issue," he said, during a tour of the transport facilities organised for the media.
"Thanks to the Games, this huge budget became guaranteed," he said. Crucially, at a time of deep public spending cuts in Britain, that budget is protected from political and economic pressures.
"At the end of it, there will be a legacy," said Stephens. "All London transport will be significantly reinvigorated."
The focus of the construction of transport facilities is the Olympic Park, housing the main stadium and most of the other venues, in Stratford, a formerly depressed area of east London.
Stratford station, which 250 000 people will pass through each day, has been completely refurbished, and forms part of Europe's biggest shopping mall.
During the Games, a high-speed rail service called the Javelin will run from St Pancras International station in central London to Stratford, where spectators will have just a short walk to the Olympic Park.
The Javelin will take just seven minutes on the St Pancras-Stratford International section of track normally used by a high-speed train.
While they wait for the construction work to be completed ahead of the Olympics, Londoners have to contend with constant closures of the Underground, and frequent breakdowns.
"Everything will be ready on time," is the message from the TfL representatives.
London's newspaper, the Evening Standard, takes a gloomier view, predicting a city gridlocked for the fortnight of the Games and transport "chaos".
On the second floor of TfL's headquarters, an army of technicians and engineers is at work, trying to predict what will happen next year.
On computer screens, they run simulations day-by-day and road-by-road of how the traffic - trains, cars and buses - will move during the Olympics.
Their overriding concern is prioritising the journeys of the 50,000 competitors, officials and VIPs.
Garrett Emmerson, who is coordinating the traffic operation, said "one of the big challenges for us is that so much of the Games are happening right in the heart of the city."
The marathon will pass by some of London's most important landmarks, the beach volleyball will take place at Horse Guards Parade, near the Houses of Parliament, and the triathlon will be held in Hyde Park.
The engineers masterminding the flow of traffic will be able to control 3 000 traffic lights in an effort to keep the cars and buses moving.
But TfL is relying on a more audacious strategy by trying to convince 30% of Londoners to work from home, with the agreement of their employers.
The work-from-home plan, as well as the rest of the transport strategy, is revolutionary - and the rest of Europe is watching closely to see if it works.
"Thanks to the Olympics, London has become a test laboratory for mass transit," said Nathalie Leclerc, of Intermodes, a French company which promotes what the industry calls "intermodal transport" in Europe.
She said Stratford station was already an internationally recognised example of what laymen might call joined-up transport.
Olympics spectators will find overground trains, Underground trains, buses and taxis waiting for them, while those inspired by the Games will be able to store their bicyles there.