BERLIN - Christians, Muslims and Jews, all praying under the same roof - that's the groundbreaking project of a pastor, a rabbi and an imam in Berlin.
Still a sand-strewn vacant construction site, St Peter's Square in the centre of the German capital will - God willing - by 2018 host a building that's so unusual it doesn't have an official term.
Not a church, nor a synagogue, or a mosque as such, but a bit of all three, the centre known currently as a "House of Prayer and Learning" will be unlike any other religious venue in the world, its initiators say.
The aim of the 44-million-euro ($60-million) project, whose fundraising was recently launched but has been several years in the making, is not only to show the importance of multi-faith dialogue but to mirror multi-cultural Berlin.
"It seemed to us that there was a very strong desire for the peaceful coming together of the religions," said Roland Stolte, one of two Protestant representatives on the board of the association behind the project.
Not by coincidence, it will stand at a location with a strong and long religious significance.
In 2007 archaeological excavations unearthed the foundations of four previous St Peter's churches that had stood on the site at different periods since the Middle Ages, Stolte told AFP in an interview.
The last one, which had a striking 100-metre-tall (328-foot) steeple and dated from the mid-19th century, was damaged in World War II and later demolished by the former East German communist state in the early 1960s.
A car park then occupied the site which the city authorities later handed back to the local Protestant community.
"We wanted to revive this place, not by building a church again but by constructing a place that says something about the life of religions today in Berlin," Stolte said.
Nearly 19 per cent of Berlin's 3.4 million residents described themselves as Protestant, according to 2010 official data.
Some 8.1 per cent said they were Muslim and 0.9 per cent Jewish, while more than 60 per cent said they did not adhere to any religion.