Here’s one potential pan-European high-speed rail map, incorporating existing and likely future high-speed lines in France, Spain, Britain and Italy; the lines I’ve argued Germany should be building; and plausible and semi-plausible extensions into Eastern Europe.
Here’s a small version of the map:
For full-size 56 MB link, click here. Blue lines exist or are under construction, red ones are either under planning or proposed solely by me or by local activists.
The Polish network is fairly optimized, but the rest of Eastern Europe isn’t, relying on long-range international connections that may or may not flop due to a possible international trip penalty. I only took it up to a point, so yes, there’s that link via (North) Macedonia and Kosovo, but I drew the line at some point and did not add a line from Warsaw up the Baltics and under sea to Helsinki; the Baltic capitals just aren’t big enough, and the light at the tunnel, Helsinki, isn’t big enough either.
Note also that some cities gain through-tracks on this map that they don’t currently have, especially Paris. This is to be a four-track system connecting Gare du Nord to Gare de Lyon and Gare de l’Est to Gare Montparnasse; since there’s no chance of building the main station under Les Halles this side of the 1970s, the station would have to be at a somewhat skew location relative to city center, most probably around where Gare du Nord and Gare de l’Est are now. Additional cities with notable through-tracks: Milan, Rome, Munich, Florence; Madrid gets through-tracks but those are already under construction as part of the third Cercanías axis, at typically low Spanish costs, and Marseille gets through-tracks as is the plan for the mixed classical/LGV system for Provence.
The trip times are always net of station dwell times and short timed connections at major junctions, so they can be added across the map. In Germany I sat down and figured out frequencies, running consistent stopping patterns every half hour; this doesn’t work Europe-wide, as some places are too low-density and have to make do with hourly patterns, like Eastern Europe (and, if it keeps its baroque fare system, Spain).