It is an unusual tribute to the victims of the Holocaust, but the "Stolperstein" now has widespread support within Germany - including from Chancellor Angela Merkel. Created over 20 years ago by German sculptor Gunter Demnig, the Stolperstein is a small cobblestone-sized memorial - literally a stumbling stone - faced with brass, bearing the name of a victim, and inserted into the pavement outside his or her last home.

For 120 euros, anyone can sponsor a stone as a symbolic gesture to commemorate their family member, friend or neighbour.

A total of 883 German cities have chosen to pay respect to victims in this distinctive way. But, in Munich, the cradle of Nazism, permission has been repeatedly refused.

Demnig, a non-Jewish Cologne-based artist, understood that the tragedy of Europe in the mid-20th century was compounded by the fact that Holocaust victims no longer had even a footprint in the homes they had owned, in a country where they had once felt secure.

So he came up with the idea of the Stolperstein, which would include the words hier wohnte (here lived) in each memorial - along with the victim's name, the year of their birth and the dates (if known) of their deportation and death.

Today, his artwork constitutes the largest project of commemoration of the Shoah in the world.

Demnig's idea emerged from his view that it is not sufficient to confine the testimony of Holocaust victims to Jewish museums.

He wanted passers-by to understand to whom these homes once rightfully belonged - and perhaps spend a moment contemplating that missing footprint linking each house to its original owner

Demnig's idea took root in December 1992, the 50th anniversary of Heinrich Himmler's edict to send Sinti and Roma to extermination camps.

Demnig erected the first Stolperstein outside Cologne's historic town hall, engraved with the decree's first sentence. And he vowed to commemorate all victims of Nazi persecution in front of their last place of residence.

But although 48,000 of these stones have now been installed in 18 European countries, commissioned by the victims' descendants, the city burghers of Munich have consistently banned them.

Their reasons are complex, and not entirely about antisemitism, since the Stolperstein honours all victims of Nazism. Many neo-Nazis campaigned against them but some Munich Jews also object, fearing that passers-by treading on these stones could be said to be stamping on the dead.

Opponents have opted instead for the city's state-of-the-art Jewish museum as a more fitting memorial. But Munich residents who support the Stolperstein argue that museums and disused synagogues in Eastern Europe in effect realise Hitler's cynical pledge to commemorate a dead culture.

So they remain prohibited on public property. Most victim groups have condemned the ban as both "shameful and shaming" and have urged the municipal government to overturn it.

Vociferous advocates of the Stolperstein include Angela Merkel, Germany's President, Joachim Gauck, and the President of the Central Council of the Jews in Germany, Dr Josef Schuster, with leading colleagues.

Noted supporters in the Jewish world include Rabbi David Ellenson, president of the Hebrew Union Congregation - Jewish Institute of Religion, and Rabbi Baroness Julia Neuberger, who lost family members in the Holocaust, and felt more affected by the thousands of Stolpersteine clustered in Berlin than by the large Holocaust monuments to the murdered Jews.

"Even more movingly this is not a government-sponsored initiative" she says. "Each stone is paid for by the residents of the house above, once lived in by Jews, and schoolchildren take on finding out about the individuals and families. The stones say very little. Name, dates, what happened; murdered or died of disease and starvation.

"But there's a sense that the present-day Berlin population has recognised that the memories of those absent people lie just beneath the ground in Berlin, and these tiny memorial stones you can't fail to stumble over keep the memory alive."

However, Munich-born Charlotte Knobluch, one of Germany's most prominent Jewish leaders, takes the opposite view: "Do you want a Holocaust memorial to be trampled underfoot? It's irreverent."

In 2008, an award-winning documentary by Dorte Franke, Naming the Names, showed the artist working on the pavements of Germany and Austria, travelling from Berlin to Vienna and Budapest, where he was constantly challenged by surprised onlookers.

Watching him create each concrete cube, 10cm across, and then cover it with a sheet of brass clearly disturbed his compatriots. In the film, he elicits sympathy from a group of German women who take it on themselves to polish each stone carefully, ensuring that the name is not missed. One woman remarks: "It should be our parents standing here, not us."

The views of other passers-by echo Munich's policy, which is firmly rejected by Demnig. The reason he chose to handmake each tribute stone, he insists, is because the Nazi death machine was based on a production line of enslavement and death.

Munich's decision provokes considerable soul-searching. As the Germany of today opens its hearts to those fleeing terror abroad, does the Stolperstein offer a genuine opportunity for reparation?

Or is it simply an insult to the victim's memory?

Baroness Neuberger has no such qualms. To her, it is "a memorial that really works, and the motive behind these stones, plus the way they are done, is just perfect."

Whatever the eventual outcome in Munich, the Stolperstein is surely a powerful and unique recognition of the meaning of home.

And perhaps even more important, it is a tribute to that visionary artist who took it upon himself to convey what man's inhumanity to man really means.