A ceremony has been held in the German capital, Berlin, to mark the beginning of work on a national Holocaust memorial.
The first of 2,700 concrete slabs were laid after the project was held up by years of debate over the design, location and cost.
The memorial is being built in the centre of the city, close to the Brandenburg Gate and near the bunker where Nazi leader Adolf Hitler committed suicide in 1945.
The US architect behind the project, Peter Eisenman, said the memorial was "about the people who are not here and we shouldn't forget that".
About six million Jews were murdered in Europe under Nazi rule.
'Feelings of loss'
The concrete pillars will be laid out in a plot of land the size of two football pitches.
It will give the impression of a vast graveyard. An information centre attached to the monument will be built underground, directly beneath it.
The memorial is being built in the heart of Berlin
Mr Eisenman says the design will force people to confront the past by evoking feelings of loss and isolation.
"You'll feel like what it is to be alone," he said. "You will feel what it is like to be lost in space. I talked to people who walked alone at Auschwitz, who saw their parents taken away, who felt lost to the world."
The memorial was approved by the German parliament in June 1999.
Bulldozers started levelling the site earlier this year.
The monument should be completed by May 2005 - in time for the 60th anniversary of the end of the World War Two.