Ancient open-air theatres across Greece are crumbling due to neglect and need swift government intervention to rescue them, archaeologists said on Thursday.

Greece, where Classical drama was born in the 5th century BC, boasts scores of theatres that form a key part of the country's classical cultural heritage. But while about 30 are in a state to host cultural events, 76 are in need of urgent repair, they said.

"Ancient theatres need to be constantly preserved, some need to be restored, but what they mostly need is to be used," classical archaeology professor, Petros Themelis told Reuters.