You can book your EuroStar tickets at
EuroStar
Just a glance at the timetable for the 14th and 15th of February, I see departures/arrivals/durations at:
0534 0923 2h49m
0634 1023 2h49m
0709 1059 2h50m
0812 1147 2h35m
0909 1253 2h44m
1010 1359 2h49m
1040 1417 2h37m
(and later)
and return trips at:
(earlier trips and ...)
1743 1925 2h42m
1816 1958 2h42m
1919 2054 2h35m
2043 2228 2h45m
Fare for Standard SemiFlexible from London Waterloo Int to Paris Nord is $120.50. The return trip is $157.50.
The last time I was at the train station there, I decided I was going to do that someday. I think it would be a fun way to go.
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