The Brusio spiral viaduct is a unique railway bridge located in the Swiss canton of Graubünden. The viaduct was built between 1906 and 1908 as part of the Albula Railway line, which is known for its steep grades and tight curves.

The viaduct is a stunning engineering feat that consists of a single spiral loop that allows trains to climb or descend a steep mountain grade in a relatively short distance. The viaduct spans 110 meters and has a height of 32 meters. It is made up of six stone arches that support the railway tracks as they spiral around the central pylon.

The Brusio spiral viaduct is not only functional, but it is also a work of art. The bridge's unique design and impressive engineering have made it one of the most photographed and iconic landmarks in Switzerland. The viaduct has been featured in numerous movies, television shows, and advertisements and is a popular destination for train enthusiasts and tourists.

Visitors to the Brusio spiral viaduct can take a scenic train ride on the Albula Railway line and experience the bridge's impressive design up close. The railway line passes over the bridge several times, offering passengers a unique perspective on the spiral loop and the surrounding mountain landscape.