'Spectacular' 149km-long train route is one of Europe's best - but follow important tip

A stunning that passes through southwestern Germany, through pine forests and postcard-perfect towns, has been named one of best adventures. Passing directly through the Black Forest, the route is 93 miles long and ascends some 2,130 feet.

The Baden Black Forest Railway ("Badische Schwarzwaldbahn") is a twin-track electrified railway line in Baden-Württemberg. It runs in a northwest-southwest direction to link the city of Offenburg on the Rhine Valley Railway (Rheintalbahn) with Sigen on the High Rhine Railway (Hochrheinbahn). It remains the only true mountain railway in to be built with two tracks, built around 160 years ago.

On its journey, the passes through an impressive 39 tunnels and over two viaducts. By cutting through the forest, the trip between Offenburg and Singen was shortened from 149 miles to 93.

The route is currently operated by a regular service of Deutsche Bahn RegionalExpress trains, using double-decker rolling stock, allowing for excellent views of the countryside, which varies from grassy fields, deep green pines and towards the shores of Lake Constance.

From Offenburg, the train quickly leaves urban life behind, swapping it for open fields with their skylines pierced with church spires from the various clusters of villages. From the city of Hornberg, the view from the window transforms to one of dense, dark foliage.

Finally, from Donaueschingen the route runs right down to Singen, where it joins the Upper Rhine Railway to continue to Lake Constance, fed by the at the northern foot of the Alps.

About an hour and a half into the route, Donaueschingen makes a good pit stop. The birthplace of the , one of Europe's longest and mightiest rivers, visitors will find plenty of places to tuck into hearty Black Forest dishes such as the Schwarzwalder Shinken (ham) or Kalbsrouladen (veal roulade).

From the vivid and charming city of Freiburg, it is only a one-hour train ride through the impressive Höllental ("Hell Valley"). The town of Triberg, meanwhile is famous for its waterfalls.

A key tip is to ensure you get a seat early, to increases your chances of going on the upper deck, which makes for even better views of the German landscape.

As an added bonus, according to , this is a regular service doing a scenic route, meaning your Interrail Pass is valid on this train. This is a pass for European, and UK, citizens which allows unlimited travel on trains and ferries within 33 countries across Europe. Four days of unlimited travel in one month is currently available for just €212 per person.

According to , other rail tickets of interest include the Baden-Württemberg Ticket. This rail pass allows 24 hours of unlimited travel in the state in second class on regional trains. It costs €24 per person.