Environmentalists are planning a major protest campaign to stop Athens 2004 organizers from building an Olympic rowing centre on marshlands next to the ancient battleground of Marathon.
Building two artificial lakes on the ecologically fragile land would threaten historic sites and wildlife, said Demetres Karavellas, chief executive of the World Wildlife Fund Greece.
If the plan goes ahead, he warned that environmentalists would turn the Schinias area into a hotspot of Olympic protest.
"We will need contingency plans to deal with bulldozers on site," said Karavellas. "But it is easy to organize something quite feisty."
The campaign to move the Olympic rowing competition away from Schinias is also backed by Europa Nostra, which groups cultural heritage foundations from 30 nations.
"It was a shock for all those interested in European culture," said Europa Nostra chairman Daniel Cardon de Lichtbuer. "It is one of the most important cultural landscapes in Europe."
For the 2004 Games, organizers plan to dig two channels some 2.5 kilometres long for the rowing and canoeing competition.
Stands for 14,000 fans, towers, athletes' facilities and parking lots would turn the area into an ecological wasteland, the environmentalists claimed.
The WWF said the project violates EU directives on protecting wildlife habitats and said the EU's executive Commission should use its powers to force Greece into leaving the area untouched.
It wants the Commission to block EU funds for Olympic construction until changes are made.
Environmental groups want the competition moved from Schinias to Iliki, an artificial lake about 70 kilometers northwest of Athens.
In 490 B.C at Schinias, the Battle of Marathon took place, with the Greeks driving the Persians back into the sea and scoring a stunning victory.
The story of the messenger who ran to Athens to spread the news of victory and died on the spot lies at the origin of the marathon race. The 2004 Olympic marathon is expected to start from the historic site.
"There is this tragic irony in returning the Olympics to Greece and destroying this one site that gave the name to the marathon," said Karavellas.