The 99 km. single track railway from Bologna to Pistoia, which takes its name from the resort of Porretta Terme, was the first railway to link the provinces of Tuscany and Emilia-Romagna through the Appennine Mountains, and was an important factor in the creation of the Italian state. It was also known as the Transappenninica or Strada ferrata dell’Italia Centrale (the central Italian railway). There were many disputes about railway routes in the region in the 1840s and 50s when the authorities of the Habsburg Empire were concerned about the military implications of new lines, but by 1864, when the line opened the Habsburgs no longer had any influence in this part of Italy. The line’s engineer was Jean Louis Protche (1818-86) who was born in Metz, studied in Paris and subsequently made his home in Italy. The line had 47 tunnels and 35 major bridges and viaducts. The 26 km. section between Pistoia and Porretta climbs some 550 m. Protche’s most important innovation was the spiral tunnel between Piteccio and Corbezzi built in a way that foreshadowed the methods used on the Gotthard and other railways through the Alps. The line was extremely busy in the nineteenth century, and particularly during the First World War, and it was electrified in 1927, but in 1934 long-distance traffic was diverted to the”Direttissima”, the newly-completed direct line between Bologna and Florence. The Porrettana was severely damaged in the Second World War but was re-opened in 1947, and, in spite of threats of closure, continues to carry local passenger trains. Its 150th anniversary was enthusiastically celebrated in 2014. The tourist office publishes a walking guide which enables visitors to see the main engineering features of the line.