The Eurostar train between London and Paris or Lille is a super cool way to get across the English Channel. The train passes through the channel tunnel or “chunnel” much more quickly than going through the airport or taking the ferry. Compared to SNCF (the French railway), it is amazing.
I was scheduled to catch the 8 a.m. train from St Pancras Train Station in London the morning after Stage 3. I was out late the night before so I did not rise in time to check my email. I missed the email from Eurostar telling me that due to mechanical difficulties and repairs in the tunnel, I needed to reschedule to a later train. A ticket concierge helped me reschedule and I had a couple of hours to get a bite to eat and get through security.
The St Pancras station’s (across the road from Kings Cross Train Station) Eurostar loading area is fairly small and probably due to the maintenance issues was very crowded. Once we loaded onto the train it was a very comfortable 2.5 hour ride to Lille. I did not even feel the pressure in my ears when we entered the tunnel. The only way I could tell I was under the English Channel was the dark windows.
Later I received an email offering me a partial discount for the inconvenience. On SNCF I encountered crabby ticket sales people, nonexistent train conductors, closed cafe cars (for the duration of a 4+ hour train trip), and overcrowded passenger cars. I tried first class and second class. The only difference was the color of the seats and plugs for recharging phones.
My chunnel experience from Paris to London was excellent. I already blogged about my misadventure getting to Gare du Nord. Once I got to the station and found the Eurostar entrance I received excellent service. The ticket concierge helped me change my ticket to the next train without a penalty. This time security and waiting was easier. It seemed like we were in London in very little time.
I will definitely use the chunnel again if the opportunity presents itself and recommend it to fellow travelers.
americanjulie.com 
I’ve travelled on the Eurostar, but not from London to Paris. The thought of travelling UNDER the ocean is quite intimidating to me. I’m glad you enjoyed the trip!