Egor Aleev/TASS
The trip from Kazan to Bilyarsk is 137 kilometres (85 miles) on Trassa R-239 (R-239 Highway). You have to drive towards Orenburg, to the ferry across the Kama River near Sorochyi Gory Village, take the bridge and head left, towards the village of Alexeyevskoye. After the village, turn right, following the signs, and drive a further 45 kilometres (28 miles) on to Bilyarsk. Buses for Bilyarsk leave Kazan twice a day and you can also get there by hydrofoil.

The village of Bilyarsk stands on the site of Bilyar, the "Great City" of Russian chronicles. It was the ancient capital of Volga Bulgaria, and is believed to have been one of the world's largest cities in the Middle Ages, exceeding Paris and London both in area (800 hectares) and in population (70,000 people). The city was famed as a large industrial and commercial centre, the meeting point of the caravan routes from Central Asia and Iran, Kievan Rus' and Scandinavia, the Caucasus and Byzantium. The city was destroyed during the Mongol conquest of 1236. Those of its residents that were left alive moved to other towns and villages in the Kama and Volga regions.

Today, Bilyar is a collection of ancient architecture dating from the 10th to the 12th centuries. It is the site of an archaeological dig that has already resulted in the discovery of the remains of a white-walled Cathedral Mosque with an area of about 2,500 square metres (27,000 square feet), a palatial complex, fortifications, Bulgarian aristocratic houses and a caravanserai.

The Bilyarsk Open-Air Museum includes a Museum of History and Archaeology, a memorial house in honour of Russian chemist Alexander Arbuzov who founded the scientific school of organophosphorus chemistry, the site of the ancient city of Bilyar, and the Holy Spring, which was considered a pagan sanctuary as far back as the ninth century. There are plans to open a Museum of History and Ethnography.