ATHENS, Greece (AP) — Authorities in Athens announced the closure of the Acropolis for five hours on Wednesday due to heat wave temperatures that also shut many schools.

The ancient site in the Greek capital — which drew nearly 4 million visitors last year — was closed from midday till 5 p.m. as the temperature was set to reach 39 degrees Celsius (102 degrees Fahrenheit).

Elementary schools and preschool classes were also canceled in parts of southern and central Greece where the temperatures were highest.

Conditions worsened in an area north of the capital, after a fire at a cookware and food container factory sent clouds of thick black smoke into the sky. Cellphone alerts sent by a government disaster response agency urged residents in the area to remain indoors.

In Athens, city authorities announced that garbage collection would also be halted for several hours Wednesday and that seven air-conditioned spaces would be opened to the public. Drones with thermal cameras were being used in Athens to coordinate the public health response, officials said.

Cooler weather is expected late Friday.