Unparalleled, nation-wide coverage has virtually turned China’s high-speed rail network into a giant version of a city’s metro grid.
These trains run at 300-350 km/h, while being both a lot cheaper and more convenient than flying.
When the next generation of 600-km/h maglev trains come fully into service, there’s going to be no point in flying at all.
There are tunnels going underneath the water between mainland Europe and England. The Channel Tunnel for railway is 50km long which by train takes up to maybe 15 minutes I think.