To the west of where the pyramid is today was another royal palace, the Tuileries, and it was a long-term ambition of the later French kings to link up both residences with two parallel wings, creating a great central courtyard.

BBC: Classic sights in the City of Light

Security at royal residences had already been stepped up after an Australian writer paraglided onto the forecourt of the Queen's central London home Buckingham Palace on 28 December.

BBC: Alert as palace security breached