Steered by his 1913 Continental Railway Guide, Michael Portillo travels one of the most stunning rail routes of the world, through the former Russian empire from the Black Sea to the Caspian Sea, taking in present-day Georgia and Azerbaijan. Following the historic Trans-Caucasus Railway, Michael begins in the port of Batumi on the dazzling Caucasian Riviera. He savours the soul of Georgia in its wine and discovers a surprise 19th-century tea plantation in the West Georgian countryside. The seat of power beckons in Kutaisi, home to the wonderful glass dome built for the Parliament of Georgia when it moved here from the capital, Tbilisi, in 2012. At the medieval convent of Gelati Michael sees how magnificent frescoes are being painstakingly restored and finds out about the most powerful king in Georgian history.