The Olympic Stadium was designed precisely to avoid becoming a "white elephant" after London 2012, but with three weeks to go to the Games, its future remains uncertain.
London's key pledge when it won the hosting rights in 2005 was that the stadium would provide a lasting athletics legacy for the city, rather than join the embarrassing collection of abandoned Olympic venues in past host cities.
The functional, no-frills stadium is designed to meet that pledge. It is designed as a permanent 25,000-seater sunken athletics stadium, with a temporary 55,000-seater tier on top, the bare concrete exterior of which is covered in a fabric wrap.
The upper tier's temporary design means that catering facilities and toilets are located outside the stadium.
The venue in Stratford, east London, cost £486 million ($760 million, 600 million euros) and was a statement of intent that this Olympic stadium was not going to be a waste of money.
Its plain design is a marked contrast to Beijing 2008's striking Bird's Nest stadium -- now more of a tourist attraction than a sports venue.
Bids to find a buyer for the stadium were sought and West Ham football club -- who are based in east London -- won the contest, edging out north London Premier League rivals Tottenham.
However, the decision hit a wall of challenges from rival bidders and, facing legal deadlock, the process was abandoned in October 2011.
Seeking a resolution, the stadium was kept in public hands and the process restarted in January, with prospective tenants now vying for a 99-year lease from 2014.
The 2012 Games organisers were "absolutely determined" that the venue should have a long-term future, said Tessa Jowell, Britain's Olympics minister from 2005 to 2010.
"We were all haunted by the possibility of our stadium being a 'white elephant'," she told AFP.
"Central to our bid was a promise that there would be an athletics track in legacy," she explained.
"Therefore we envisaged a multi-use stadium with athletics at its heart... that would maximise its use by including other sports and activities.
An 80,000-seater stadium might only be needed once a year and was thus not deemed sustainable, she said.
"We were determined that the stadium would be reduced to a size after the Games that would be useful and practical in legacy," she said.
But while the future uses of most of the London 2012 venues are secured, the Olympic Stadium's destiny is still far from resolved, with the Games just weeks away.
Three contenders have confirmed their bids, with applications due to close in early July.
They are West Ham, a joint bid by University of East London and Essex cricket club, and a company wanting to stage a Formula One race that would go inside the stadium.
East London football side Leyton Orient also retain an interest.
"It remains our intention to sign construction contracts for converting the stadium at the end of October," Andrew Altman, the outgoing chief executive of the London Legacy Development Corporation, said in May.
Altman is to leave his post after the Games, with The Daily Telegraph saying he had "effectively paid the price for failing to secure the future of the stadium".
Having won the abandoned contest to buy the stadium, West Ham might now consider themselves in a stronger position, having won promotion back to the lucrative Premier League.
The club acknowledges that the bid to move has divided fans who are loyal to its Upton Park home, 2.5 miles (four kilometres) away from the Olympic Stadium.
Football played in athletics stadia is commonplace elsewhere in the world but none of England's 92 league teams do so -- the closeness to the pitch is seen as essential to the atmosphere.
Tottenham's bid involved demolishing the stadium and building a football-specific venue, while paying towards redeveloping the dated Crystal Palace athletics stadium in south London to uphold the athletics legacy pledge.
The club's ground is five miles (eight kilometres) away, triggering claims that they would have been invading West Ham's territory and abandoning their traditional home community.
But third-tier football side Leyton Orient, whose home ground Brisbane Road is the closest at 1.5 miles (2.5 km) away, also complained bitterly about the threat to their "patch" posed by West Ham moving in.
Their challenges helped trigger the collapse of the original West Ham deal.
Orient chairman Barry Hearn has branded the venue "not fit for football" -- the low rake of the seats gives a flat view -- but still wants the tenancy if seats can be put over the track.
The stadium is due to host the 2017 World Athletics Championships, meaning it should remain in its current two-tier format for the short-term.
"I'm absolutely sure that the right long-term use will be found," Jowell said.
"Probably by this time next year there will be a long-term tenant... and this will be a living stadium, probably with football, probably as an entertainment venue with other uses as well."