Stop on the London-Paris train (6)
I believe the answer is:
calais
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">stop on the london-paris train</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for calais that I've seen before include "French port opposite Dover" , "Northern French port" , "French Channel port" , "French port for ferry to England" , "A ferry port in northern France" .)