Berlin Letter Derek ScallyThree men rattle collection tins in the blazing sun at Berlin's largest fruit and vegetable market. An old man stops to ask what the collection's for. When he hears that they are raising money for the new mosque being built around the corner, he gives a dismissive wave of his hand and hurries away with a stricken expression.
"Everyone will be welcome. The mosque is not directed against anyone although some older people seem to feel that way," says Ali, one of the collectors.
Like Christian churches in centuries gone by, the modern-looking mosque has been financed by around €3 million in donations.
Another €2 million in donations and bank credit will be needed to complete the project by early next year.
Still shrouded in scaffolding, the raw concrete structure with large windows has yet to be cladded in sandstone and fitted out inside with a mosque as well as shops, cafes and function rooms.
Two minarets are already in place on the roof, an unusual sight on the Kreuzberg skyline until now dominated by the red-brick turrets of local churches.
"There is so much rubbish going around about Islamic terrorists that it is important to come out into the open where we can interact with people," said a fundraiser in a cabin outside the mosque who declines to give his name.
Forty years after the first immigrant workers arrived from Turkey, Germany's Muslim community is making itself visible like never before.
Until now, the country's 3.2 million Muslims worshipped in provisional mosques hidden away in disused factory buildings and in the courtyards of apartment blocks.
"The first generation of immigrants just wanted somewhere to pray because in the back of their heads they were always ready to return to Turkey," says the fundraiser.
"The new mosques are a sign that the second and third generations are more prosperous and see Germany as home."
As thousands of Catholic and Protestant churches in Germany close every year, dedicated mosques are sprouting up around the country, changing forever the city landscape and often stirring up resentment.
Some 200,000 Muslims live in Berlin and attend Friday prayers at the city's 72 mosques.
The newest mosque opened last year, a huge building in the old Ottoman style with 28m-high minarets and lots of marble and ornamentation.
It is a huge architectural departure from the fascist pomp of the nearby Tempelhof airport and was the subject of long-running resident protest.
Residents objected to the Kreuzberg mosque too and planning officials forced the architect to revise a design they saw as "too oriental".
German Islamic experts have warned that the organisation behind the Kreuzberg mosque rejects integration in favour of a strict Islamic lifestyle in so-called "parallel societies".
Decades of apathetic tolerance between Germans and Muslim immigrants ended in 2001 when it emerged that the September 11th attacks were planned by Islamic extremists in Hamburg, who took advantage of German laws prohibiting police monitoring of groups registered as religious organisations.
Those laws have since been revised and now mosque raids are a regular occurrence, angering Muslims who complain that a stigma of suspicion hangs over them.
Adding to the tension has been the new media interest in so-called "honour killings" in Turkish-German families and a recent television expose of an extremist imam who ranted to his Berlin flock about German "atheists . . . who don't shave under their arms. The sweat gathers there and creates a terrible smell, a stink".
The emergence of German Muslims from their courtyard mosques is being met with increasing protests.
Last week, over 2,000 people marched against plans to build a new mosque in the eastern Berlin neighbourhood of Pankow.
Reservations can even be heard in the multicultural neighbourhood of Kreuzberg, known as "Little Istanbul" because of its large Turkish community.
"I'm not sure I like it," said Stefan, a passerby gazing up at the new seven-storey mosque. "I'm against organised religion generally because they are oppressive structures. This is so big and in-your-face."
Local planning official Frank Schulz, who gave the green light to the mosque, rejects criticism of his decision.
"In planning law, who you pray to doesn't play a role," he said.