Ah! A bridge! Brilliant! 
Rick Steves called it “a hundred-mile-an-hour non-event,” and that is pretty much what my experience was back in 1998. That doesn’t keep you from sort of expecting something more exciting, though.
I’ve done it about a dozen times now, and I never feel completely comfortable knowing there’s that there’s that much rock and water above me. There was an occasion recently where there was an electrical fire and some poor bastards ended up stuck in the tunnel for several hours. Not my cup of tea.
I therefore time the tunnel bit with getting and eating food. Stroll to the buffet car, grab one of their surprisingly delicious cheese and ham flatbreads, stroll back, take my time eating it, and then I’m in the daylight in France.
Everyone’s mentioned the terrible color scheme of the upholstery (all I can think is it must have been a French designer), but the other thing nobody’s mentioned is the smell: there’s a very strong, slightly musty smell of minerals and water coming through the aircon the whole time the thing is in the hole.
ETA: it only does 60mph in the tunnel, but once it gets to France, holy shit does it go fast. 180mph cruising speed makes the countryside warp.
Sounds like a longer version of riding the BART across the bay.
“Previews” of the new domestic high-speed services from St Pancras to Kent have started. They use part of the same high-speed line that Eurostars do, some going to Ebbsfleet and others going to Ashford.
I had a go on one last week (for work purposes). The journey to Ebbsfleet takes all of 17 minutes, much of it in tunnels. The (Japanese-built) train goes at full speed all the way - the acceleration is tremendous. Ashford is just 37 mins compared with over an hour on a “normal” train.
I’ve been on the Eurostar on four round trips from London (twice to Brussels, twice to Paris). It’s boring, yes, but it’s zippy, much better than the long-distance trains within Britain* and a helluva lot more convenient than plane or ferry.
- On that note, DO NOT ever take Grand Central Trains. Wow, do they ever suck.
Hardly.
Killarney’s about fifteen miles from the Atlantic coast. I know Ireland is small, but it’s more than fifteen miles across.
But a Eurostar train is a lot more comfortable than BART. But it’s not a lot more exciting. I did it 13 years ago. I’ve done the ferry also (not the hovercraft) and the train is a lot more efficient.
I’m a claustrophile, so no problem for me, but the speed in France made me a bit motion sick if I looked out the window. I didn’t have that problem with the bullet trains in Japan for some reason.
Having done both, the Eurostar is much more comfortable and predictable than the old hovercraft. The Channel can get really rough, and the hovercraft would be cancelled well before the ferry in such conditions.
I have been in the Eurostar when it stopped in the middle of the tunnel for about 10 minutes with no announcements. Didn’t bother me, but my slightly claustrophobic friend was not at all amused. I actually found it quite cool to be stationary, knowing that I was under the sea between two countries.
In general when being transported, “boring” tends to be good. Especially since the alternative is often “terrifying.”