Steam trains continue to run on the Harzer Schmalspurbahnen narrow-gauge line, and their trips through the snowy landscape on the Brocken mountain - northern Germany's highest peak - is often a spectacle that draws curious tourists.

Spanning more than 130km, the Harzer Schmalspurbahnen is the country's largest network of narrow-gauge railways.

With Germany's reunification and the merger of the two state railway systems, many had feared that the narrow-gauge steam railways would not survive.

Yet, despite services elsewhere in the country being replaced by diesel or electric trains, carriages on this line are still hauled by powerful steam locomotives, which provide a public transport lifeline in a part of Germany that still seems rooted in the last century.