Greece has been grappling with extreme weather this summer and a week-long heatwave - its worst in 30 years
* Suburbs north of Athens threatened by fires
* Hundreds evacuated by boat from Evia island beaches
* Forests devastated, animals killed as flames advance (Updates with man killed, new fires, evacuations, details)
By Lefteris Papadimas and Costas Baltas
ATHENS, Aug 6 (Reuters) - Police went door to door on Friday urging people to leave their homes north of Athens and emergency crews struggled to stop wildfires from spreading to more towns as scorching winds fuelled blazes across Greece for the fourth day.
Greece, like much of the rest of Europe, has been grappling with extreme weather this summer. A week-long heatwave - its worst in 30 years - has sparked simultaneous wildfires in many parts of the country, burning homes and killing animals as flames tear through thousands of acres of land.
At least 56 active fronts burned across the country on Friday, from the Peloponnese in the west to the island of Evia near Athens, where hundreds of people had to be evacuated by boat as flames burned through forestland to the shore.
"The fire in Attica is dangerous. It's unpredictable," the head of Greece's firefighters federation, Dimitris Stathopoulos, told Skai TV, referring to the wider region which includes the Greek capital.
Thousands of people have fled their homes since wildfires on the foothills of Mount Parnitha just north of Athens burst back into life late on Thursday, and authorities ordered the evacuation of several suburbs.
"We might have to spend the night in the car if we don't find a friend to host us," said Yorgos, 26, who had to leave his home in the suburb of Polydendri.
The fire, which broke out on Tuesday, burned around the main highway linking Athens to northern Greece and hundreds of firefighters with water-bombing aircraft battled to contain it.
"Conditions are extremely dangerous," Deputy Civil Protection Minister Nikos Hardalias said.
A 38-year-old man was killed on Friday by a falling electricity pylon in a suburb north of Athens, the hospital where he was treated said.
In neighbouring Turkey, authorities are battling the country's worst-ever wildfires, and flames sweeping through its southwestern coastal regions forced the evacuation of tens of thousands of people. In Italy, hot winds fanned flames on the island of Sicily this week.
Temperatures have been over 40 degrees Celsius (107 Fahrenheit) all week and no let up came on Friday with high winds spreading the flames further.
The Athens power grid operator announced staggered power cuts in the surrounding region to ensure there were no major outages in mainland Greece.
In Gytheio in the southern Peloponnese, a coast guard vessel rescued 10 people from a beach on Friday as a blaze there flared. Locals made desperate calls for firefighting aircraft.
In the Peloponnese, where firefighters saved Ancient Olympia, the site of the first Olympic Games, from a fire this week, the flames left behind scorched earth and dead animals.
"A catastrophe," said farmer Marinos Anastopoulos. "The fire came around midday with swirling winds and homes were burned, a lot of animals burned to death. Rabbits, sheep, dogs, everything."
On Evia near Athens, coastguard vessels assisted by tourist boats have picked up 631 people since late Thursday from three beaches on the island, where the flames have burned through a vast area of pine forest since Tuesday and reached the sea.
(Additional reporting by Angeliki Koutantou, Karolina Tagaris, George Georgiopoulos, Giorgos Moutafis and Rami Ayyub; Writing by Karolina Tagaris; Editing by Giles Elgood, William Maclean)