Sentence:  The country has, in effect, installed a “keep out” sign over the white cliffs of Dover. Even as Mr Cameron defends the City of London as a global financial centre, and takes planeloads of business folk on foreign trips, his government ratchets up measures that would turn an <WSD>entrepôt</WSD> into a fortress. 
Meaning of the word marked with <WSD> tags:  A point of entry for people, especially immigrants, into a city or country.