ATHENS — The buildings constructed in Athens for the Olympic Games four years ago are fly blown, closed to the public, and covered in graffiti, a forewarning of the possible aftermath of the London Games in 2012.

Of the 22 venues in the city, 21 are in a state of disrepair and under guard to prevent vandalism.

Athens spent more than $18 billion on staging the Olympics, slightly less than the current estimate for the London games.

The hangover from the games was tremendous. Greece was left with a national budget deficit of 6.1%, more than twice the maximum allowed under European Union rules.

The infrastructure, which was installed in such haste, has proven to be far too extravagant for the city. It is difficult to imagine there was ever much local interest in continuing to use the baseball, kayaking, fencing, and handball facilities down the coast at Hellenikon.

A few miles outside the city center, the sprawling Faliron complex that once hosted the beach volleyball and taekwondo competitions is deserted and a lone security guard has not been able to deter youths from spraying the walls with slogans.

Inside one of the buildings, puddles of water are dotted across the marble floor.

The baseball stadium was briefly used for football matches, until the organizers realized that the shape of the baseball diamond resulted in all the television cameras standing at the corner flag.

Elsewhere at Hellenikon, piles of rubbish are mounting behind heavily padlocked gates and electrical cables hang loose from the walls. On one bridge, every light fitting has been wrenched out, while crumbling concrete is ubiquitous, a sign of the speed at which the complex was built.