International connections and obstacles

The experience of regular travel with standard tickets and that of Interrail leisure travellers will be very different due to the way that ticketing is handled.

In many ways the modern method of advance booking and demand driven fares, low-cost airline style, is at odds with the open interrail ethos and is producing some serious problems due to the way certain operators are dealing with this.

A number of the issues that occur regularly on these forums simply do not apply to non-interrail travel which is the vast majority of rail users in Europe.

While I am not minimising the issues faced by interrailers, it is however a small part of the rail travel market and one which neither the Air or long distance Bus operators offer any equivalent to as they have long abandoned anything other than pre-booking by individual segment.

Quite a complex question. 

When it comes to interconnectivity between the biggest cities, it's usually okay. Pity that the choice kinda always leads you towards high speed trains. And sometimes billions are being spent on a new high speed line, but heavily underused. The TGV's France-Barcelona are a fine example of this. Getting to Scandinavia is also difficult, although investments are being done. 

What I find more annoying is the lack of proper regional trains, going over country borders. For example in Belgium,  no real complaints of getting to London, Amsterdam, Cologne, or Paris. But the rise of high speed trains came at the expense of smaller, regional connections.

Why is there no train between Hamont and Weert (Nl), Gent-Terneuzen (Nl) , De Panne and Dunkerque (Fr), Mons-Quiévrain-Valenciennes (Fr), Dinant - Givet (Fr) , Hasselt-Maastricht(Nl),... ? These connections could mean so much for locals and the regional economy and sustainable transport. 

And where there are some cross border options, it's ridiculously expensive. Just for crosqing an imaginary line? Ordinary tickets Antwerpen Breda, e.g.

Of course you have a zillion different railway safety technologies, different voltages and gauges. But that doesn't explain why you had some classic, logic intercity or eurocity connections until a few years ago. It just disappeared. We used to have Eurocities from Brussels to Switzerland until 10 years ago. Now we're obliged to use much more expensive high speed trains, taking a geographically absurd route.

Crossing borders in Europe has become much easier for almost every other transportation means, but a lot smooth, regional, train connections disappeared over the years. 

Sustainable travel options only seem to be encouraged in words, yet proper policy choices and infrastructure investments don't seem to follow. 

Guess many other countries have as many different examples.