Imagine if Buckingham Palace or Beijing's Forbidden City were put on the market. How much do you think they would cost? Get ready for your jaw to drop as we reveal the (guesstimated) value of the world's 10 most opulent palaces. All dollar values in US dollars.

The only non-royal, non-ecclesiastical palace in England, the 18th-century Blenheim estate in Woodstock, Oxfordshire is the grandest country house of them all and a UNESCO World Heritage Site to boot.

The baroque palace was built by John Churchill, 1st Duke of Marlborough, between 1705 and 1722, and is the birthplace of Sir Winston Churchill. While Blenheim is open to the public these days, the current Duke and his family still reside there, albeit in a modest farmhouse on the estate.

The palace is brimming with antiques and sits in 3.1 square miles (8 square kilometres) of iconic parklands designed by Lancelot ‘Capability’ Brown. All this of course comes at a price; property expert Henry Pryor estimates the Blenheim estate is worth in the region of $235 million (£180m).

The longest occupied palace in the world, Windsor Castle dates from the 11th century and has survived 41 monarchs. Located in Berkshire's Windsor Great Park, the residence itself sprawls over 53,000 square meters and is a mishmash of Gothic, Georgian and Victorian styles.

The castle is renowned for its magnificent state apartments, considered by many experts to be some of the finest examples of Georgian style. Other highlights include the medieval St George's Chapel and a wealth of treasures, from priceless artworks to King Charles II's bed.

A fire that damaged a mere section of the castle in 1992 caused a hefty $47.6 million (£36.5m) worth of damage, so it's hardly surprising the entire royal palace is thought to be worth more than $236 million (£181m).

Turkey's new presidential palace in the capital Ankara was completed in 2014. Dubbed 'Ak Saray' (the 'White House'), the gargantuan 1,150-room complex is four times larger than the Palace of Versailles.

The pet project of President Tayyip Erdoğan, Ak Saray has been mired in controversy since its conception. Critics have lambasted the government for its extravagant spending on the palace interiors, which are packed with fine marble, lavish furnishings and expensive artworks.

Initially projected to cost $323 million (£247m), the palace went well over budget, coming in at more than double the estimate at a massive $663 million (£508m) – the glass alone is estimated to have cost $225 million (£172m).

The Istana Nural Iman Palace is the official residence of Brunei's mega-rich Sultan Hassanal Bolkiah. At a humongous 200,000 square meters, it's the largest palace in the world that's still in use as a royal residence.

Built in 1984, the blinged-out palace contains 1,788 rooms, a banqueting hall seating 5,000 guests and a mosque that can accommodate 1,500 worshippers. Luxury amenities include five swimming pools and a swish nightclub.

In total, the palace cost $1.4 billion (£1.07bn) to construct back in 1984. Taking into account inflation, it's likely to be worth about $3.9 billion (£2.9bn) today, a fairly significant chunk of the Sultan's estimated $20 billion (£15.3bn) net worth.

Now part of the colossal Hermitage Museum, the Winter Palace in St Petersburg was the official residence of the ill-fated Russian royal family. The most recent incarnation was built between 1730 and 1837, and sprawls over 60,000 square meters.

The Winter Palace contains 1,500 rooms, which are decorated in baroque and neoclassical styles, and brimming with treasures, from Egyptian mummies and classical Greek sculptures, to Old Master paintings and diamond-encrusted Fabergé eggs.

The average land price in St Petersburg's most upscale neighborhood pushes $24,000 (£18.4k) per square meter, so based on land alone, the Winter Palace is worth $1.44 billion (£1.1bn). An additional $5 billion (£4bn) should just about cover its many treasures, so in total, the palace and its contents could be worth upwards of $6.44 billion (£4.9bn).

Queen Elizabeth II's London residence dates from the 17th century and boasts 775 opulent rooms, 40 acres of grounds and plenty of luxury amenities, which include a swimming pool and stable block.

Sumptuous and suitably palatial, the fantastically ornate state rooms are decorated with antique furnishings and objets d'art, while the Queen's Gallery exhibits 450 super-valuable paintings at any one time.

Top real estate firm Foxtons has valued Buckingham Palace at $2.89bn (£2.2bn) based on its size alone. If you factor in $2.15 billion (£1.64bn) for the artworks, antique furniture, luxury amenities, and so on, the palace is likely to be worth around $5.04 billion (£3.84bn). In 2020, however, online estate agent Emoov calculated that the royal residence could add up to as much as $7.2 billion (£5.5 billion). 

The home of Japanese Emperor Akihito, Tokyo's Imperial Palace comprises the main palace structure, various museums, administrative buildings and gardens totaling 1.31 square miles (3.41 square kilometers), slap bang in the middle of Chiyoda, one of the capital's prime real estate areas.

Built in 1888 on the site of the ancient Edo Castle, the palace and its grounds were estimated to be worth more than all the real estate in the State of California during the height of the Japanese property bubble in the late 80s.

While not as ridiculously valuable nowadays, the palace is still worth an astronomical amount of money. According to official 2016 figures, premium Chiyoda properties command $33,000 (£25.2k) per square meter, so the palace and its grounds are worth $11.25 billion (£8.6bn) based on the land alone, and you can add a further billion dollars to cover everything else.

A former royal residence dating from the 14th century, the Louvre Palace was converted into a museum following the French Revolution. The palace complex occupies 2.26 million square feet (210,000 square meters) in the centre of Paris.

The Louvre counts some of the world's most famous – and valuable – works of art in its collection, including Da Vinci's Mona Lisa, which is said to be worth up to $1.5 billion (£1.1bn), as well as a vast array of priceless antiquities.

According to French historian Patrice de Moncan, the Louvre minus its contents is worth a staggering $10.5 billion (£8bn). The museum's 35,000 artworks and 380,000 objects have a likely minimum value of $35 billion (£27bn) so, in total, the Louvre and its contents would set you back $45.5 billion+ (£35bn+).

The world's largest royal domain comprising over eight million square meters of grounds, Versailles was transformed from a regal hunting lodge into a spectacular palace by Sun King Louis XIV during the late 17th century.

The palace features 700 rooms – including the stunning Hall of Mirrors – housing 5,000 pieces of antique furniture and 6,000 notable paintings, while the grounds boast 400 sculptures and 1,400 fountains. No wonder Versailles has been declared a UNESCO World Heritage Site.

Land costs around $5,000 (£3.8k) per square meter in the town of Versailles, so the value of the palace's land alone is $40.7 billion (£31.1bn). The building itself and contents are likely to worth another $10 billion (£7.6bn), so Versailles could in all likelihood be valued at $50.7 billion (£38.8bn).

The crown jewel of Beijing, the Forbidden City was the residence of the Chinese emperors and the locus of government from 1420 to 1912. Now a museum, the complex was declared a UNESCO World Heritage Site in 1987.

The palace complex is made up of 980 buildings, crafted from wood in the traditional style, dotted over 728,000 square meters of manicured grounds. They showcase over a million rare and valuable works of art.

Land prices are as high as $27,000 (£20.6k) per square meter in the much sought-after area surrounding the Forbidden City, so the total price of the land alone amounts to $19.66 billion (£15bn). If the average work of art is worth just $50,000 (£38.2k), the entire contents of the Forbidden City would be worth more than $50 billion (£38.2bn) so, along with the land, the total value would be $69.66 billion (£53bn) plus!