Originally built in the early 1980s, the renamed Athens Olympic Sports Complex (OAKA) received it’s biggest renovation for the 2004 summer Olympics by famed architect Santiago Calatrava. Like most of Calatrava’s work, the OAKA is stunning and graceful—but today is in a state of dereliction and disrepair.

Athens’ Acropolis and Byzantine styles inspired Calatrava’s immense work, which cost over $10 million. Parts of OAKA are still in use, mostly by local sports leagues, and following 2004, sections were turned into worker housing. The former communication center is now government ministry offices and the badminton hall was converted into a theater venue.

Like many large Olympic arenas, the Olympic Stadium of Athens, known as the “Spiros Louis,” is occasionally used as a large-scale concert venue; since 2004, Madonna, Bon Jovi and U2 have played there.

Two streets in the complex were named after Greek Olympic medalists who themselves fell into disgrace. Konstantinos Kenteris, who withdrew from the 2004 games after failing to take a doping test (he claimed to have missed the test after sustaining injuries in a motorcycle accident, but an official investigation later proved the accident was staged) and Fani Halkia, who tested positive for methyltrienolone in the 2008 Olympics of Beijing and was subsequently banned.

Today, the complex as a whole is empty and unkempt. It’s open for visitors, though you may be the only one visiting. Examining the velodrome’s soaring arches contrasted against rusting pools, broken fountains, and weed-filled stadiums all sprawling out over 96 hectares leaves one amazed how such a project declines in less than a decade.

OAKA’s fate is not unfamiliar to Olympic stadiums. Travelers who’ve visited the disused stadiums of other past Olympics may find resonances—particularly Barcelona’s 1992 Olympic Stadium, only partially used today and, curiously, the site that made Santiago Calatrava famous for the telecommunications tower he designed. Like his Olympic complex in Athens, the telecommunications tower of Barcelona stands largely forgotten, remembered mostly by those who visited during the games and the few who visit today.