I've been planning a trip pretty similar to this for years, and like to think that I would have done it in summer 2020 had COVID not happened (my planned route is Skye-Bali and involves a couple of ferries so not 100% train).<p>I cosign everything in the OP article regarding logistics, current availability, the Vientiane Gap, etc. The only thing I'd note is that there's a different route available that is about 1000km shorter, via Barcelona-Nice-Milan-Venice-Vienna-Bucharest-Istanbul-Baku-Astrakhan-Almaty-Urumqi-Kunming-etc.<p>I've done nearly the full Trans-Siberian and while it's a cool experience (esp if you speak Russian and can talk with people on the train), watching pine trees go by gets boring after day 3. I personally think that if you're going to commit to a Europe-Asia train trip, it's better to take the scenic route.<p>The even more exciting option will be when China finishes the Dushanbe-Kashgar and Lhasa-Chengdu railways. That will facilitate an absolutely epic ride through the top of the world.