For 75 years the French Senate - the upper house of parliament based in the historic Luxembourg Palace - has been keeping an embarrassing secret.
Hidden in the basement, its whereabouts privy to just a handful of initiates, lies a bust of Adolf Hitler.
This week the bust's existence was revealed thanks to an investigation by Le Monde newspaper. It also found a 3m x 2m (10ft x 6.5ft) Nazi flag, and various other documents and items from the Occupation.
Reporter Olivier Faye said he heard on the grapevine that a Hitler statuette had been kept in the Senate since the end of World War Two, when the palace was the headquarters of the German air force (Luftwaffe).
Le Sénat dissimule dans ses caves un buste d’Hitler et un drapeau nazi depuis soixante-quinze ans https://t.co/qPXUzNWlKA— Le Monde (@lemondefr) September 3, 2019
After much stonewalling from officials he finally had confirmation from the Senate's chief architect, Damien Déchelette, who asked him: "How ever did you find out?"
Why was the bust still hidden?
The exact story of how the bust and flag came to be secreted in the bowels of such an important public building remains a mystery. But the outline of events can probably be guessed pretty accurately.
In August 1944 Paris was in turmoil as the German army fought and then surrendered to the combined forces of the French army and Resistance.
In the Luxembourg Palace, fleeing Luftwaffe personnel left a scene of chaos, with walls smashed and furniture in piles. It was the same in the adjoining building known as the Petit Luxembourg, then the residence of German air force commander Hugo Sperrle, now of Senate president Gérard Larcher.
According to historian Cécile Desprairies, for the liberating French it was a moment of ecstasy. "Flags were taken as trophies. Buildings were pillaged. The liberators took whatever they could of the occupier. The black market in Nazi goods flourished - and indeed it is still there."
Somewhere in the disorder, someone at the Luxembourg Palace must have put to one side the Hitler bust and the flag. They were covered up and hidden in the basement, and knowledge of their existence was then passed on over the years among a small group of staff members, after the building resumed its functions as the Senate.
Contacted by Le Monde, no serving or former senator was aware of the Nazi mini-trove. But as one anonymous Senate official told Olivier Faye, "Senators come and go". They are not the real repositories of the building's lore.
"I imagine that every now and then those in the know would come and have a glimpse at them, to give themselves a little frisson," says Olivier Faye.
What else remains from the war?
Less secret - but still little known and certainly off-limits to visitors - is an underground concrete bunker in the gardens of the Petit Luxembourg. This was built before the war as an air-raid shelter for parliamentarians, and was used possibly as an office or for storage by the Germans.
The bunker is itself a fascinating time-capsule, containing such curiosities as a "cyclomotor" for charging batteries with pedal-power in the event of a blackout, rubber protective suits for gas attacks and a wartime radio set.
There are also two German military relics: a box containing a breathing apparatus, and another containing a gas-powered lamp.
In answer to Le Monde's enquiries, the Senate finally produced an inventory of what it says are all the German items in its possession. These also include a large number of documents and various items of furniture stamped with the eagle of the Third Reich.
What to do with this cumbersome Nazi inheritance has now become a sensitive issue.
Senate President Gérard Larcher has ordered an investigation. One likely destination is Paris's new Museum of the Liberation at Place Denfert-Rochereau, whose centrepiece is the underground command bunker used by Resistance chief Henri Rol-Tanguy.