There's a proposal for a high speed rail line in Europe that would connect Vienna, Bratislava, and Budapest, the capitals of Austria, Slovakia, and Hungary. By fascinating geographic circumstances, all 3 capitals are very near the national borders with the other countries, meaning that the 3 cities are actually quite close together:
-Vienna to Bratislava: 55km (about the same distance as Toronto-Hamilton)
-Bratislava to Budapest: 160km (about the same distance as Toronto-Belleville)
-Vienna to Budapest: 215km (about the same distance as Toronto-Kingston)
These relatively short distances are enough that a high speed rail connecting all 3 cities can basically transform them into a single transnational metropolitan area. It will be fascinating to see if it ever gets built. Though it looks like the kooky hyperloop fetish has hit them too, unfortunately.
https://www.dezeen.com/2016/03/11/hy...enna-budapest/