Watch Great Continental Railway Journeys Season 4 in Australia

Armed with his trusty 1913 Bradshaw's Continental Railway Guide, Michael Portillo travels east through the Balkans along the most exotic section of the route taken by the Orient Express. His journey begins in Sofia, capital of Bulgaria, and includes stops in the ancient city of Plovdiv, the region of Rumelia, and former capital of the Ottoman Empire Edirne. Arriving in Istanbul, Michael takes a trip on the Bosphorus - a much-coveted stretch of water - finds out about Turkish delight and travels along the Marmaray metro line, which connects European and Asian Istanbul via a tunnel beneath the Bosphorus.

In Vienna, Michael Portillo encounters a pre-Cold War spy and learns about the concert that caused a riot in 1913. He then travels the Habsburg imperial line across the Semmering Pass, a line blasted through the Alps. In Graz, the former politician ventures underground at the Lurgrotte Caves to find out about a famous rescue operation of the past, then in Slovenia discovers how an earthquake in Ljubljana prompted its citizens to assert their national identity in architecture and art. Arriving in the Italian port of Trieste, Michael savours the imported coffee that fuelled a cafe culture.

Bradshaw's 1913 Continental Railway Guide in hand, Michael Portillo visits Italy, where he experiences first-hand the nation's need for speed in a state-of-the-art Maserati sports car. Michael discovers how the leaning tower of Pisa was rescued from near collapse. In Carrara, he finds out how the marble used by Michelangelo is still quarried today and is invited to chip away at a contemporary sculpture. In Bologna, he embarks on a doomed search for spaghetti Bolognese until a cookery teacher shows him how to make a much more authentic tagliatelle al ragu. Following in the footsteps of Bradshaw's travellers, Michael explores the cradle of the Renaissance through Edwardian eyes. Heading north to Gargnano, Michael discovers the romantic hideaway of one of Britain's most famous writers, DH Lawrence, whose affair with his professor's wife scandalised his home country. Michael ends his journey in futuristic style with a high speed boat trip across Lake Garda.

Armed with his 1913 Continental Railway Guide, Michael Portillo embarks on a Greek odyssey from Athens's port of Piraeus north to the city of Thessaloniki, captured the year before from the Ottoman Turks, who had ruled much of Greece for 400 years. Exploring the Acropolis and delighting in the tastes of moussaka and baklava, Michael discovers the many influences at play in the creation of modern Greece - from its classical past to the oriental Ottomans and the great European powers of Britain, France and Russia. Along the way, Michael discovers the parlous state of Greek finances at the time of his guidebook. He learns how an aristocratic English poet became a Greek national hero and relives Greek athletic victory at the first modern Olympic games.

Armed with his 1913 Continental Railway Guide, Michael Portillo ventures deep into the Black Forest on a quest to discover the essence of Germany and discovers how Hansel and Gretel helped to unify the nation. A humbling masterclass in carving cuckoo clocks shows him how the nation's reputation for quality and reliability in manufacturing was established from the early 18th century. A romantic stop at the ruined Schloss in Heidelberg follows before Michael gets an insider's guide to share dealing on the Frankfurt Stock Exchange. At Goettingen University, Michael discovers two sides of student life at the turn of the 20th century - the duelling fraternities and the groundbreaking scientists who laid the foundation for Germany's world class transport technology today. Braving the force of the Goettingen wind tunnel, Michael investigates the track where model trains are fired at up to 360km per hour.

Steered by his 1913 Bradshaw's Guide, Michael Portillo returns to Spain to trace the early 20th-century roots of the Spanish Civil War, which divided his Spanish family and sent his father into exile. He discovers a nation fractured at the time by social tensions and regional loyalties, which today offers a rich diversity of cultures to delight the tourist. Special dispensation to fly to the Balearic island of Mallorca allows Michael to spoil himself rotten with spectacularly scenic rides aboard a sublime 1912 vintage railway and a 1913 tram. On his travels, he is trampled underfoot at the bottom of a Catalan people steeple and learns to make the perfect paella. He pays homage to the genius of Barcelona's most famous architect and meets the man responsible for finishing off Antoni Gaudi's life's work. And he discovers a beautiful art nouveau Palace of Music with an emotional history.