A 17th-century oil painting has been found behind a wall in a Paris store, and it's not the only treasure that's been unearthed after years, sometime centuries, of being hidden. From paintings gathering dust in attics to pots of coins discovered in the garden, these incredible treasures have been rediscovered in the most amazing circumstances.

In September 2014, a small box filled with gold and silver jewellery that had sat undisturbed since 60AD was found buried beneath the Fenwick department store in Colchester, England. The box turned out to be a priceless Roman treasure trove of international importance and is currently on display in Colchester Castle.

Australian farmer Stuart Dunbar was lucky enough to accidentally find one of the biggest black truffles reportedly ever grown in Australia. Truffles are already a pretty pricey ingredient, so it comes as no surprise that the fungus, weighing in at 1.5kg, was valued at AUS$3,700 (US$2,700/£2,082). Dunbar described it simply as "a beast".

Ever thought you could quite literally be sitting on a fortune? Well a couple from Scotland did just that. Angela Milner-Brown and her husband Angus discovered jewellery worth $6,485 (£5,000) hidden inside an old dusty chair they’d bought for just $6.50 (£5) at an auction 10 years previously.

In 2007, an impoverished German student lucked out big time when she found a 17th-century oil painting in a shabby old couch she'd snapped up for just €150 ($171/£132) at a Berlin flea market. The painting was eventually sold for a whopping €19,600 ($22,328/£17,215) at auction.

A hoard of 19th-century US gold coins were dug up in a garden in Hackney, London in 2009. Worth $104,000 (£80,000), it was later discovered that the coins were buried just before World War II by a Jewish family fearing a Nazi invasion of the UK. The treasure was eventually claimed by a descendant of the family.

In 2014, as part of a documentary called Atari: Game Over, excavators unearthed 1,300 ET games cartridges at a landfill site in New Mexico, which had been unceremoniously dumped after the infamous title bombed in 1983. Incredibly the games have generated $108,000 (£95,000) in sales from buyers from around the world. The money went to the Tularosa Basin Historical Society.

In May 2013, builder David Gonzalez snapped up a dilapidated property for just $10,100 (£7,787) in Elbow Lake, Minnesota, which he intended to flip for profit. Gonzalez' bargain purchase paid off and then some. While knocking down a wall, he discovered a copy of Action Comics Issue 1 worth $175,000 (£135k).

Contractor Bob Kitts accidentally unearthed a couple of years’ worth of salary in a bathroom wall during a job at an Ohio house. Behind the walls sat $182,000 in Depression-era currency. Unfortunately he only ended up with a few thousand after a lengthy court battle with the homeowner. Still, a couple of thousand is better than nothing.

A 110-year-old piano was the unlikely hiding place for a hoard of over 900 gold sovereign coins, the largest-ever haul of such coins in the UK. The upright piano had been donated to Bishop's Castle Community College in Shropshire in 2016, and while the college's piano technician Martin Backhouse was working on it he found the coins stored in white corduroy pouches lying underneath the piano's keys. The hoard was valued at $648,500 (£500k).

An 18th-century bust of a British politician, Sir John Gordon, was discovered propping open the door to a shed in the village of Balintore, Easter Ross in Scotland. Valued at more than $1.9 million (£1.5m), it has now been displayed in the Louvre.

In 1992 a farmer living near Hoxne in Suffolk, England lost a hammer in his field, so asked a friend to try to find it using their metal detector. They didn’t find the hammer, but they did find a host of coins, spoons, jewels and statues dating back to the Roman Empire. The farmer and his friend were paid $2.3 million (£1.75 million) for the haul, which is now on display in the British Museum.

In 1989, a man in Philadelphia picked up an old painting at a flea market for $4 (£3), simply because he liked the frame. Investigating a tear in the canvas, the frame fell apart in his hands and a folded document fell out. It turned out to be an old copy of the Declaration of Independence and was sold at a Sotheby’s auction for an incredible $2.42 million (£1.9m)!

Michael Rorrer was cleaning out the Virginia home of his great aunt, who had recently died, when he discovered her husband’s old comic book collection. This wasn’t just any old stack of Archies though – half of the collection was auctioned off in 2012 and raised an incredible $3.5 million (£2.7m).

A Frenchman who inherited a property in Normandy from a relative who had died discovered an enormous collection of thousands of coins and bars weighing more than 220lb in 2016. “It started when he found screwed under a piece of furniture a tinplate box (with gold inside),” according to La Dépêche, the local newspaper. His next find was inside a “whisky bottle box with a few gold pieces carefully hidden.” The find gradually grew, and he has since sold it all for €3.5million ($4m/£3.1m).

When Dr Harold Carr passed away in 2009, he left his niece and nephew the deeds to his dusty garage in Newcastle, England in his will. When they opened it up they discovered their eccentric uncle had stored a 1937 Bugatti Type 57S there, which had once been owned by British aristocracy. It fetched a cool $4.2 million (£3.2m) at auction.

In 2010, architect Todd Ernst uncovered a mural by artist Keith Haring while renovating his home in New York City's Tribeca neighbourhood. The home, complete with artwork still in place, was sold in January 2015 for a cool $10 million (£7.7m)

A couple from Northern California struck gold (literally) when they discovered a pot of rare gold coins buried in their back garden. The pot, which had been hidden away during the 19th-century Gold Rush, contained 1,427 mint condition coins with an estimated value of $10 million (£7.7m).

A painting by artist Norman Rockwell was discovered behind a false wall owned by the late cartoonist Don Trachte Jr when his sons were renovating their father's property. The painting had been hidden by Trechte Jr to avoid his wife being granted it following their divorce in 1970. It later sold at auction for $15.4 million (£11.9m).

A treasure trove of 60 rusting classic cars was discovered on a French farm in 2014, worth over an incredible $25m (£19.3m). The cars were collected from the 1950s to the 1970s by entrepreneur Roger Ballion, but his haul sat dormant in corrugated iron shelters on the farm after he hit financial problems. One Ferrari 250 GT SWB California Spyder was previously owned by French film star Alain Delon and sold for €16.2 million ($18.5m/£14.3m) alone.

When Thomas Schultz and Lawrence Joseph bought a cottage in Long Island, New York, they discovered a massive haul of paintings in the attic. The collection, which was painted by the little-known Arthur Pinajian, has now been valued at an incredible $30 million (£23m).

In 2014 a 400-year-old painting, believed to be by the Italian master Caravaggio, was discovered hidden in the roof of a house in Toulouse while repairs were carried out. The painting is currently on the market and valued at as much as €120 million ($137m/£106m).

During the construction of the new Oscar de la Renta Paris store in Paris, builders got more than they bargained for. Behind a wall they uncovered a 10-by-20-foot 17th-century painting by a Flemish painter called Arnould de Vuez. Why was it there? It's suspected it was hidden to prevent Nazi looters from taking it during the Second World War.