The stone viaducts of Switzerland's world famous Rhaetian Railway were built around 1900. They are still in use today, serving the modern railway practically unchanged. In 2008, the Albula Line became a UNESCO World Heritage site. But after more than a hundred years in service, the viaducts are in need of renovation. Building Switzerland provides an insight into the country's most spectacular architectural and engineering feats in recent history. This 13-part video series looks inside architecturally important buildings, discovers hi-tech design, opulent and surprising living spaces and amazing bridges, and talks to the people who gave them life.