Olympics 2012

The guards outside the abandoned Olympic venues in Athens were not happy when we turned up with our camera.

It's pretty depressing for the organisers of the 2004 Games to see some of the arenas, which they built with pride, now covered in weeds and locked away behind high fences. It is costing more than £1m a month just to keep them maintained.

Four years on from the Games, this is an Olympic tour the big cheeses in the International Olympic Committee are not taken on.

It's a shame because what has happened in Greece is a sobering reminder to London 2012 of the dangers of not getting all the legacy plans in place before the show even hits town.

The taekwondo, wrestling and sailing venues around Athens look well designed but they are simply not being used by the public regularly. The weeds are growing high at the sailing venue. This isn't what they mean when they talk about "Green Games."

Constantinos Cartalis, a former minister of culture who was responsible for drawing up the legacy plans for Athens, told me he's sad that some of the venues have been turned into shopping malls. He wanted a sporting or cultural legacy for the city.

Now in opposition, he believes the current Greek government has not followed through with the promises he made. There is no overall systematic plan, he believes.

His message to London is: "Get all of your legacy ducks in a row before the Games begin".

The market, he says, doesn't wait for dithering politicians. Although the main Olympic complex is well used, Athens can't find permanent tenants for some of its venues. The momentum of the Games has gone.

London 2012 has still yet to find a tenant for the main stadium in Stratford. There is talk of Leyton Orient or a rugby club like Saracens or Wasps being persuaded to move in.

The government and London 2012 keep saying they are serious about a long-lasting legacy.

But my tour of Athens tells me one thing: London 2012 has to get the commercial or tenancy deals for the arenas signed and sealed well before the opening ceremony.

The danger, if they don't, is a repeat of the Athens scenario.