The Queen and Prince Philip travelled by Eurostar from Waterloo to Paris for a State Visit.
The three-day visit to France marks the centenary of the Entente Cordiale encouraged by Edward VII who spoke French and paid an historic visit in 1904.
The Queen also speaks French and will be delivering her public speeches in the language of her host President Chirac.
On the train with Her Majesty were 300 British school children who are visiting France as part of the recent Franco-British Education agreement.
This is the Queen's fourth State Visit to France. The eralier visits were in 1957, 1972 and 1992. Paris was the first foreign destination of the newly married Princess Elizabeth and Prince Philip in 1948.
This is the Queen's first trip through the Channel Thunnel since the rail link was inaugurated a decade ago.
As part of the Entente Cordiale celebrations President Chirac will pay a return State Visit to the Queen in London this autumn.