We travelled today into Italy from Switzerland using the Simplon Tunnel; a great piece of engineering from the early 20th century (the first tunnel was finished in 1906 and the second in 1921).
It’s a great way to get across the alps using an environmentally friendly electric powered rail service in open sided carriages; hugely atmospheric with a cacophony of sound (especially if you leave your windows open, rather like riding on a full sized ‘ghost train’) . The engineering was pioneering at the time with two 20km parallel tunnels (the second to provide air to the workers which was later upgraded to a full working tunnel) and was dug from each side and met in the middle only inches out of alignment. But as you travel give a thought to the appalling condition for the Italian workers (working in temperatures up to 42℃), many who died during the construction and later from disease, and when they went on strike were forced back to work by Italian vigilantes and the Swiss army!
On leaving the tunnel you arrive at Iselle station which has an amazing time warp feel to it, as if you are in war time Europe. A setting I hope to use in fictional work based in that era pulling in other aspects of Northern Italy at the time.