A wildfire was raging Monday on the coastal front of Athens, officials said, with summer homes under threat and a local village evacuated.
The fire in Kalamos, about 45 kilometres (28 miles) east of the Greek capital, was burning across a wide front for a second day and had already burned a number of homes.
There were no immediate reports of injuries.
A force of more than 200 firefighters with over 100 fire engines, water trucks and a handful of aircraft had been mobilised, the fire department said.
"It's a strong fire in an area full of summer homes," civil protection official Ioanna Tsoupra told ERT television.
The local municipality of Oropos had earlier urged residents to evacuate for their safety, and a monastery was also emptied.
The fire service said they were battling two additional blazes on Monday, one near Thessaloniki, the country's second-largest city, and another in the southern Peloponnese peninsula.
"The fire near Thessaloniki is almost under control but we are worried about the new fire in the Peloponnese, around Amaliada, because it's very close to a village of 150 inhabitants," a spokesman told AFP.
Overall, 91 fires had broken out in Greece since Sunday, the fire department said, though most were quickly brought under control.
The other flashpoint is the tourist island of Zakynthos in the Ionian Sea, where emergency crews have struggled to put out a wave of fires since last week, and officials suggest arson is at play.
"Such a situation is unheard of," regional fire chief Vassilis Matteopoulos told ERT.
"We had 22 fires on Zakynthos just in the last 24 hours."
Greece is routinely hit by wildfires at this time of year, fanned by strong winds and high temperatures, and authorities have warned that the risk remains high.
The worst recent major blazes, in the Peloponnese and on the island of Evia in 2007, left 77 people dead and ravaged 250,000 hectares (620,000 acres).