On which popular routes in Europe is train travel cheaper than flying?

[BECKHAM]

Travelling by train on certain routes in Europe can be twice as expensive as taking a plane, even if flying is far worse for the climate, Greenpeace has denounced. But on some common routes, the train is still the most affordable option.

for more... (https://www.thelocal.ch/20230725/on-which-popular-routes-in-europe-is-train-travel-cheaper-than-flying)