Really really really big. (You may have to think even bigger and use Chrome or something else to translate the whole article from German to your happy language). Here’s an excerpt:

“…The economists are calling for the establishment of an “ultra-rapid train” that will connect major European cities with an average speed of 250 to 350 kilometers per hour. One route should run via Lisbon, Paris, Berlin, Copenhagen to Helsinki. The Paris-Berlin route would be halved to around four hours by the express train, the economists write.
“There will be a total of four such European express train routes. Thanks to its geographical location in the heart of Europe, Germany would particularly benefit from the establishment of such a network. Even fast train journeys to the outermost edge of Europe, for example to southern Italy or the Baltic States, would be possible.
“The move from plane to train would reduce Co2 emissions by four to five percentage points, according to the analysis. As more freight traffic could be handled by rail at the same time, this would further reduce emissions from road traffic.”

This is more an exercise in moving the goalposts than engaging with reality, methinks.

But stranger things have happened.

Also I: Jesus frick that automatic translation to English is spectacular.

Also II:

“The 18250 km route would cost around 1.1 trillion euros.”

Cheap as chips!