If you like behind-the-scenes infrastructure videos, you might find the BBC’s The Channel Tunnel — Life on the Inside interesting.
Olivia and I travelled from Paris to London through the Chunnel in 2009; it was the final leg of a rail journey from eastern Slovakia right across Europe. My lasting memory of the Eurostar trip is not infrastructure-related, it’s Olivia’s considerable consternation about Parisian kiosks not selling English-language kids magazines. By the time she’d calmed down we were in London for a rendezvous with our friend Jonas and a pop-in at Platform 9¾.
When you first posted this, I added the four part series to my watch later list on YouTube. I finally got around to watching them over the last couple of days. Very enjoyable. Thank you for the recommendation.