Thefts from nearly 600 Jewish cemetaries were paved over over by communist officials until being unearthed by a Czech journalist
The cobbled streets of Prague are much romanticised by the visitors to the Czech city.
The rugged streets and cold war charm of the Bohemian capital attracts some 7.6million visitors annually, making it one of the most visited cities in Europe.
But few realise what they are walking upon a dark secret.
Leo Pavlat – journalist and director of the Prague Jewish Museum – has made it his mission to leave no stone unturned in bringing this mystery to light.
, Rob Cameron met with the curator in Wenceslas Square and saw some of his museum's most unusual artefacts.
Cubes of polished granite – like the millions paving the pedestrian streets throughout Prague – are indistinguishable when lain face down.
But on the polished reverse of these Czech cobbles are fragments of Hebrew lettering and dates.
During the late 1980s in communist-era Prague these stones were used to repave the streets.
Their existence provides a theory as to the fate which befell hundreds of Jewish gravestones that went missing over these decades.
The headstones are carved into perfect cubes, now objects of macabre beauty.
The story has caught the imaginations of visitors from around the world, including Chinese artist Ai Wei Wei. The artist, whose own work features ceramics packed with dark irony, tweeted out a link to the story on Sunday.
30 years ago, Pavlat made the discovery while working not far from Wenceslas square.
"It must have been shortly before Gorbachev came, because I remember they redid the cobblestones here especially for his visit," he told the BBC.
As a member state of the Soviet Union, the repaving was an effort to spruce up the city before the 1989 visit from the Russian General Secretary.
Catching a glimpse of the lettering and the dates on the reverse side, it appeared they had come from a 19th Century cemetery. He pocketed the stones as a testament to the crime.
Leo Pavlat, who was born in 1950s Prague to a Jewish family, is aware of the difficult history of anti-semitism in the city.
During the Second World War, the Jewish-Czech population shrank from 350000 to a meagre 50000.
Having barely survived Nazi occupation, the community were subjected to the slow extinction encouraged by the controlling communist government.
With anti-religious fervour and encouraged voluntary emigration, by the 1980s the population had yet again reduced to just 8000.
"There were no publications, no education. I think the regime just wanted the Jewish community to slowly die," he told the BBC's Rob Cameron.
The headstones of the country's untended cemeteries - which held hundreds of years' of Jewish history - were seized by a darkly pragmatic and repurposed as building materials.
"I don't think it was done deliberately by the Communists, to offend us Jews. But it is insensitive," said Pavlat.
While the process of pulling up the cobbles would be costly, and reconsecrating the headstones impractical, there has been call for something to be done to increase awareness of the story.
Pedestrians in the busy shopping district might soon be made aware of the uncomfortable truth on which they tread - with the help of a plaque. The cobbles might yet become a monument to the city's forgotten people, and the insensitive communist past.
The Jewish Quarter
Old Jewish Cemetery at Žižkov
Lesser known than the Old Jewish Cemetery, the Žižkov cemetery was established in 1680 during the plague. Now at the foot of the monstrous Žižkov TV Tower, it makes for a sober contrast to the communist eyesore.
Jewish Museum in Prague
The Museum is one of the city's main attractions. Spread through buildings across the original Prague Jewish Quarter, including four synagogues, the museum captures one of the best presevered examples of a medieval Jewish neighbourhood in Europe.
'Jewish Garden' or Old Jewish Cemetery
Over 600 years of crumbling headstones grow like gnarled trees in this ancient green space – earning it the euphemistic name of the "Jewish Garden". It occupies the middle of the Jewish Quarter.
One of the oldest stones belongs to the rabbi Avigdor Kara, who was interred here in 1439.
Saints Cyril and Methodius Church
This unassuming church on the corner of Zderaze and Resslova was the scene of a bloody gun battle between occupying forces and a daring Czech task-force, as retold into the 2016 Cilian Murphy film, Anthropoid.
The siege and occupation is documented in a museum below the church.
Prague's Nuclear Bunkers
As a city famous for spy swaps and espionage, Prague sits along a fault line in Cold War history. Beneath the city are several nuclear fallout shelters, built for the worryingly likely situation that Western and Soviet forces should provoke all-out nuclear armageddon.
One of these has been turned into a museum about the realities of living in the Cold War Eastern Bloc as the Prague Nuclear Bunker.
Meanwhile, another such shelter has irreverently been tuned into a venue for indoor paintballing.