An excessive heat warning has been issued by Greece’s weather service from Wednesday morning to 8pm on Thursday, with forecasts saying Athens will see conditions just below 40C (104F).
Greece has shuttered tourist hotspots and schools across Athens as the first heatwave of the summer strikes.
Temperatures were tipped to hit highs up 43C (109F) on Wednesday and Thursday in parts of the Mediterranean country.
Meteorologists say the high temperatures is being driven by southerly winds bringing hot air and dust from North Africa.
As a result, the Acropolis, the archaeological site which saw four million visitors last year, was closed between 9am and 2pm (GMT) on Wednesday over the life-threatening temperatures.
Red Cross medics were also seen handing out water bottles to tourists, while primary schools and nurseries across the southern parts of the country were closed until Friday, when cooler conditions are expected.
City authorities also shared that garbage collection would also be halted for several hours, and added seven air conditioned spaces will be opened to the public.
Drones fitted with thermal cameras will also be used in the city to coordinate a public health response.
Also on Wednesday in Athens, dozens of firefighters were battling a blaze that broke out in a cookware factory in the city on Wednesday, the Greek fire service said.
Fourteen fire trucks and 42 firefighters were sent to the incident in the northern suburb of Kifisa.
Residents in nearby areas were warned to stay indoors to protect themselves. The cause of the fire was not immediately known.
The heatwave marks the latest in a series of record-breaking weather events for Greece – one of the most climate-impacted countries in Europe.
In August last year, the country saw the biggest wildfire recorded in the European Union for 23 years at Dadia National Park in Evros.
That came just a month after wildfires broke out on the island of Rhodes. In total, 28 people died and more than 80 blazes were recorded.
Greece has also just seen its hottest winter on record, creating conditions for yet more fires this year.
One blaze broke out in northern Athens this March.
