"Outbound journey day" is what Interrail calls the day on which I leave my country to explore other European countries on rails. Going on holiday without getting in the car or on a plane – that's what I have in mind for the next two months. For the sake of the climate. And maybe also for me, so that the route is relaxed. No refueling stops, no boarding line, no navigation system, no traffic jams, no flight cancellations, no flight mode. Just get in and look out the window. In your pocket or better on your mobile phone, an Interrail pass for ten freely selectable travel days in two months. Valid in 33 countries. Domestic routes may only be used once for exit, then again for entry.

Up to the border, train travel still has something familiar: the color of the seats in the ICE, the clothing of the train attendants. The chaos when travelers want to go in opposite directions with their trolley suitcases. You know where the sockets are. Whether it's worth going to the bistro. How it sounds when the current delay is announced. Everything is well-known, you hardly raise your head. Not even for nature out there. But soon it goes through Switzerland, 15 minutes Liechtenstein, then Austria. The foothills of the Alps pass by the window. On Lake Zurich, the rails run almost at water level and close to the shore. On the right, the Glarus Alps. On the left the Walensee, petrol-coloured. At the back, the rock walls protrude like a spade leaf pierced into the water. Are people in Germany so close to the countryside and the football pitches, building material warehouses, gardens and backyards? It may be because in the mountains everything has to push through the valleys. No distance possible. We have a race with the cars on the motorway next door. Confident of victory, I lean back – and win.

Fifty years ago, Interrail was a promise of adventure and freedom. Travel without a plan and almost without money. Jump on every train for a month. I also got this free ticket after graduating from high school. The trick was to sleep on the train so that you could save yourself the youth hostels. The fact that this worked so well was also due to the old compartments, which could be converted into sunbathing lawns by removing all seats. Curtain closed and shoes off. At most, one conductor stuck his head in. And if that didn't work, there were the train stations: roll out the sleeping mat, sweatshirt as a pillow, into the mummy sleeping bag. Half a century and ten million passengers later, many things have changed: the wagons, the stations, the demands on safety and comfort. And also the system.

For three years now, Interrail has also been working digitally, via the Rail Planner app. It confirms that today is travel day, one in ten for the passport I have chosen. The system has generated a QR code for this day, which I can show as a ticket. I could have cancelled by midnight before. In the planner I have already researched connections and saved them under "My Trip", worked out a route that I can also look at on the digital map. All sliders of the routes I want to drive today are pushed to the right and therefore active. So you keep the overview. However, delays and cancellations are not displayed. For this you still need the national railway apps. Europe is not so united after all.