Local crews supported by water-bombing aircraft and reinforcements from Romania and France were operating on three fronts west of Athens in the Gulf of Corinth on Tuesday, dousing flames raging since Friday.
Strong, dry winds blowing from the Aegean Sea, known as the meltemi, had complicated their efforts, with water bombers unable to operate at times, officials said.
"We are talking about a fire where we didn't have an aircraft at our disposal for 30 continuous hours, which caused us a lot of difficulties," deputy fire brigade spokesman Ioannis Artopoios told public broadcaster ERT.
In the coastal community of Porto Germeno, some 60km northwest of Athens, Vivi Gialia, 45, surveyed the remains of her parents' home and the fire-ravaged landscape of her childhood summers.
"It's as if my heart has been torn out," she told Reuters.
Europe has been ravaged by wildfires this summer after a period of record-breaking heatwaves and little rain - conditions that many scientists say have been exacerbated by human-driven climate change.
France and Spain have been particularly hard hit, although huge blazes there died down over the weekend, providing some respite.
Greece, a known fire hotspot, had until now experienced a relatively mild summer.
Two crew members of a firefighting helicopter died on Sunday near the seaside community of Psatha, about 40km from Athens, after a mid-air brush with a second helicopter, whose two crew survived.
The circumstances of the crash, which involved US-registered Bell helicopters, were under investigation by the US Federal Aviation Administration, Greek authorities said.
At Porto Germeno, small religious shrines, ubiquitous in many Greek homes, still stood on the sides of roads or at the entrance to a gutted house.
In one home, a woman was attempting to sweep away broken tiles in a darkened room, her steel front door black from the flames.
"It was a beautiful place, we spent our summers here. We have spent happy times here, and there is nothing any more," Gialia said, criticising what she said was a slow response by firefighters.
