Samarkand

Before it was an Islamic city, Samarkand was the chief town of Sogdiana, whose merchants ran the trade between China and Iran and whose language was the working tongue of the eastern Silk Road. Sogdian religion grew from the same root as Zoroastrianism and diverged from it: the dead were exposed and their cleaned bones placed in decorated stone or ceramic ossuaries, of which many have been found around the city, and the goddess Nana, inherited from Mesopotamia, held a prominence she does not have in the Iranian tradition. Wall paintings uncovered at Afrasiab, the old mound, show ambassadors, processions and a rider on a camel, and are among the best evidence for how such a city saw itself in the seventh century.

Because Sogdians moved, so did their religions and other people's. Manichaean communities were established along the route to China, and Manichaean texts in Sogdian have been recovered from the oases to the east. The Church of the East had bishops in Central Asia and its Syriac liturgical books were copied in Sogdian too. Buddhist monasteries operated in the region and Sogdian translators carried texts into Chinese.

The Arab conquest under Qutayba ibn Muslim in 712 ended the Sogdian principalities. Conversion took generations rather than years, and the resulting city was Muslim, Persian speaking and, within two centuries, one of the intellectual centres of the eastern Islamic world.

The necropolis called Shah-i Zinda, the living king, grew around a shrine attributed to Qutham ibn Abbas, a cousin of the Prophet said to have been killed while praying and, in local tradition, to be living still beneath the ground. A lane of tiled mausoleums climbs the hillside towards it, most of them built for women of Timur's family, and the site remains a place of visit rather than only a monument.

Timur made Samarkand his capital and built at a scale his craftsmen, brought forcibly from Iran, India and Syria, could barely execute; the vast Bibi Khanum mosque began falling down almost at once. Under his successors the Registan received three madrasas facing a single square, and one of them, Sher-Dor, carries tigers and a human faced sun in tile across its front, a deliberate departure from the usual avoidance of living figures on a religious building.

Ulugh Beg, Timur's grandson, was an astronomer who governed. He built an observatory with a huge stone sextant sunk into a trench, whose arc still survives, and produced a catalogue of over a thousand stars and a set of tables that corrected Ptolemy and were used from Istanbul to India; they were printed at Oxford in the seventeenth century. Astronomy and astrology were not separate enterprises, and the tables served both. He was killed on his son's orders in 1449. Outside the city the tomb of al-Bukhari, whose collection of hadith is the most authoritative in Sunni Islam, is a pilgrimage site rebuilt on a grand scale after independence.