Vielleicht interessant, auf jeden Fall aber nützlich: ein Karte, die zeigt wie weit man in Europa in Stunden mit dem Zug reisen kann.
Hover your mouse over a station to see the isochrones from that city.
This assumes interchanges are 20 minutes, and transit between stations is a little over walking speed. Therefore, these should be interpreted as optimal travel times. The journeys might not exist when taking into account real interchange times.