By Ian MacWilliam
BBC News, in Tashkent
In an obscure corner of the Uzbek capital, Tashkent, lies one of Islam's most sacred relics - the world's oldest Koran.
The Othman Koran is the oldest in the world
It is a reminder of the role which Central Asia once played in Muslim history - a fact often overlooked after seven decades of Soviet-imposed atheism.
The library where the Koran is kept is in an area of old Tashkent known as Hast-Imam, well off the beaten track for most visitors to this city.
It lies down a series of dusty lanes, near the grave of a 10th century scholar, Kaffel-Shashi.
The Mufti of Uzbekistan, the country's highest religious leader, has his offices there, in the courtyard of an old madrassa.
Just across the road stands a non-descript mosque and the equally unremarkable Mui-Mubarak, or "Sacred Hair", madrassa, which houses a rarely seen hair of the Muslim Prophet Muhammad, as well as one of Central Asia's most important collections of historical works.
"There are approximately 20,000 books and 3000 manuscripts in this library," said Ikram Akhmedov, a young assistant in the mufti's office.
"They deal with mediaeval history, astronomy and medicine. There are also commentaries on the Koran and books of law. But the oldest book here is the Othman Koran from the seventh century."
The Othman Koran was compiled in Medina by Othman, the third caliph or Muslim leader.
Before him, the sacred verses which Muslims believe God gave to Muhammad were memorised, or written on pieces of wood or camel bone.
To prevent disputes about which verses should be considered divinely inspired, Othman had this definitive version compiled. It was completed in the year 651, only 19 years after Muhammad's death.
The Mufti of Uzbekistan has his office in the area
This priceless Koran is kept in a special glass-fronted vault built into the wall of a tiny inner room.
About one-third of the original survives - about 250 pages - a huge volume written in a bold Arabic script.
"The Koran was written on deerskin," said Mr Akhmedov. "It was written in Hejaz in Saudi Arabia, so the script is Hejazi, similar to Kufic script."
It is said that Caliph Othman made five copies of the original Koran. A partial Koran now in the Topkapi Palace in Istanbul is said to be another of these original copies.
Othman was murdered by a rebellious mob while he was reading his book. A dark stain on its pages is thought to be the caliph's blood.
The story of how the Othman Koran came to Tashkent is a remarkable one.
After Othman's death it is believed it was taken by Caliph Ali to Kufa, in modern Iraq. Seven hundred years later, when the Central Asian conqueror, Tamerlane, laid waste to the region, he found the Koran and took it home to grace his splendid capital, Samarkand.
It stayed there for more than four centuries, until the Russians conquered Samarkand in the 1868. The Russian governor then sent the Othman Koran to St Petersburg where it was kept in the Imperial Library.
But after the Bolshevik revolution, Lenin was anxious to win over the Muslims of Russia and Central Asia. Initially he sent the Koran to Ufa in modern Bashkortostan.
But finally, after repeated appeals from the Muslims of Tashkent, it was returned once more to Central Asia in 1924. It has remained in Tashkent ever since.
Visiting dignitaries from the Muslim world often turn up to see the Othman Koran in the depths of old Tashkent, so it is odd that it is still kept in such an out of the way location.
But the authoritarian Uzbek government has inherited a Soviet-era distrust of Islam, and still views much of its own Islamic history with suspicion.
The mufti's official religious establishment is closely watched and takes care not to attract too much attention to itself.
As a result, its greatest treasure, the world's oldest Koran, continues to sit quietly in the medieval quarter of old Tashkent.