Book excerpt: Thom Wheeler is not a man to be put off by the prospect of an uncharted, impractical or downright dangerous journey. Having accidentally introduced his old school friend Vicky to Dmitry, the Russian love of her life, at the Hermitage Museum in St. Petersburg, Thom decides to travel to their wedding in Astrakhan in the most obvious and straightforward way: by following the Volga river, from its source over 1,000 miles inland, all the way to the Caspian Sea and a party to remember..