The Silk Road (2016)

In the first episode of his series tracing the story of the most famous trade route in history, Dr Sam Willis starts in Venice and explores how its Renaissance architecture and art has been shaped by the east and by thousands of exchanges along the Silk Road. From Venice Sam travels to China's ancient capital, Xian. Here, Sam's story takes him back in time to reveal the tale of an emperor who was so desperate for horses to help protect his borders that he struck one of the most significant trade deals in human history - he wanted war horses, he gave the most precious material in the world, silk. From this single deal, a network of trading paths were carved out across thousands of miles by merchants, traders, envoys, pilgrims and travellers. It is known to us today as the Silk Road.

In the second episode of his series tracing the story of the most famous trade route in history, Dr Sam Willis travels west to central Asia, a part of the Silk Road often overlooked and yet the place of major innovations, big historical characters and a people - the Sogdians - whose role was pivotal to its success. In the high mountain passes of Tajikistan, Sam meets the last survivors of that race, who once traded from the Mediterranean to the China Sea. In the Uzbek cities of Samarkand and Bukara, he discovers how they were built by armies of captive craftsmen for one of the greatest conquerors the world has ever seen - Timur. From here, Sam follows the flow of goods back towards the markets of the west, showing how their trading culture sparked cultural, technical and artistic revolutions all along the Silk Road, and goes back to school to learn where modern mathematics and astronomy were born.

In the final episode of his series tracing the story of the most famous trade route in history, Dr Sam Willis continues his journey west in Iran. The first BBC documentary team to be granted entry for nearly a decade, Sam begins in the legendary city of Persepolis - heart of the first Persian Empire. Following an ancient caravan route through Persia's deserts, he visits a Zoroastrian temple where a holy fire has burned for 1,500 years, and Esfahan, one of the Silk Road's architectural jewels and rival to Sam's next destination - Istanbul. In the ancient capital of Byzantium Sam discovers how the eastern Roman Empire was ruled through silk and how Venetian merchants cashed in on the wealth and trade it generated. Sam's last stop takes him full circle to Venice. Visiting Marco Polo's house, Sam reminds us how the great traveller's book was one of the first to link East to West and how the ideas and products that trickled down the Silk Road not only helped to trigger the Renaissance, but set Europe on a path of unstoppable change.

Alfred discovers Iran; enter the city that once was the core of the entire Silk Road in Persia: Tabriz. He heads into the bazaar, the finest in the country, and wanders through its 22 miles of alleyways and stalls. Our guide meets Dr Faribouz Esmaeli at the heart of this architectural gem he oversaw its restoration. Tabriz is also the center of the ancient Armenian community in Iran.

Alfred learns that Iran has a Silk Road office. Its representative explains that the government wishes to develop links between other countries along the illustrious road. Far from the city, at 2,000 meters above sea level, Alfred visits the ruins of Hassan-i Sabbah fortress, founder of a movement known as "Hashshashins" drug smokers and killers who gave us the modern word "assassin".

In the oasis of Kashan, in central Iran, Alfred marvels at the famous pleasure gardens of Fin. At the temple of Chak Chak, in the nearby mountains, he is introduced to Zoroastrianism, Persia's ancestral religion. In the sacred city of Yazd, in southern Iran, he visits a zurkhaneh, a "house of strength", where athletes engage in training sessions.

Alfred arrives in Uzbekistan, at the heart of the ancient Silk Road. He discovers Bukhara the beautiful, dream city for numerous travelers. Home town of Avicenna, Bukhara remains the dreamland of many wayfarers through the ages. Our guide meets some of its artists and craftsmen.

Some used to say Samarkand - in central Uzbekistan - was at the center of the world. Alfred follows the ancient Royal Road to the city - associated with the great Turco-Mongol warrior Timur, who was also famed for his refinement and elegance.

Alfred is struck by the modernity of life in Tashkent, the capital of present-day Uzbekistan and a major central Asian city, and the incredible mix of ethnic groups in this part of the world. Alfred visits a silk factory - a must for anyone retracing the Silk Road, then travels the age-old route through the mountains to his next destination: Kyrgyzstan, the land of the nomads.

Osh is the first place Alfred visits in Kyrgyzstan. He saunters down the aisles of its bazaar, but soon realizes that the real Kyrgyzstan is to be found on the endless steppes and vast mountains, where you lose all notion of boundaries. Alfred learns about Kyrgyz identity from a girl student who tells him local legends at the foot of the "Throne of Solomon", the hill that overlooks the city.

Alfred's point of entry to China is Kashgar, in the Xinjiang region, which covers a sixth of country's surface area. This is the home of the Uyghurs, an ethnic minority descended from Turkic peoples. When trade on the Silk Road was as its height, Kashgar was a major hub for caravans travelling to India or Central Asia.

A Uyghur family invites our guide into their home. He learns about their way of life and growing techniques. Gaochang used to be an important waypoint through the Silk Road and a famous gathering place for scholars.

Crossing the Taklamakan desert is a demanding step. And only once the Silk Road caravans made it could they say they truly arrived in China. The Bactrian camel has become emblematic of the region: without it, trade could not have developed along the Silk Road.

Alfred travels to Liqian, at the narrowest point of the Hexi Corridor. Legend has it that Liqian is where the descendants of Crassus' lost legions ended up. From there, he goes to the sprawling industrial metropolis of Lanzhou, on the Yellow River, and samples an essential ingredient of Chinese culture - noodles.

Alfred arrives in Xi’an - in the province of Shaanxi. The Silk Road caravans used to end their long journey in this millenary city.