We all know a city that looks this good doesn’t come cheap.

However none of the UAE’s most famous landmarks take the title of the world’s most expensive – though we have one building in the top 10, and a further two in the top 20.

In a global round-up by Fly Abu Dhabi, the towering Burj Khalifa comes in as the world’s 19th priciest structure to build, ringing in at a cost of Dhs5.5b (US1.5b).

Burj Khalifa View

As the world’s tallest building, standing a proud 829.8 metres, it would take 36 workers four months to clean all the tower’s 24,348 windows completely by hand.

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As it stands, workers do clean from the 160th floor down using building maintenance units, custom-made machines that slide on fixed tracks on the Burj Khalifa’s exterior.  The process takes between two and three months, with certain isolated areas maintained by traditional rope-access cleaning.

Coming in at No 11 is the Princess Tower, Dubai’s second tallest building with 107 storeys and a cost of US$2.17b (Dhs7.9b). The Marina-based skyscraper was built in 2012 and was briefly the tallest residential building in the world, before being overtaken by 432 Park Avenue in New York in 2015.

Princess Tower

Abu Dhabi’s Emirates Palace takes the seventh spot, with its US$3b (Dhs11b) bill to build. The luxury five-star hotel was constructed in 2005, and is made up of 144 domes which measure 262 feet high.

There’s also 200 fountains, a 24-hour butler service, a separate floor reserved just for royalty, and the hotel has hosted celebrities such as Bill Clinton, Robert de Niro, Will Smith, and Michael Jackson.

Emirates Palace, Abu Dhabi

The rest of the top 20 is mostly made up of US-based buildings (athough Singapore and Macau make multiple appearances).

Given that most of the entries have been constructed in the last 10 years or so, the number one winner may surprise you – given that it’s been in construction since 638.

Al-Haram in Mecca is the largest mosque in the world, and the destination of the Hajj pilgrimage. Spanning 356,80 square metres, the Grand Mosque has incurred a US$100b construction bill in its time.

Here’s the full list of the top 20 most expensive buildings around the world:

1. Al-Haram Mosque, Mecca, Saudi Arabia – US$100b
2. Abraj Al Bait, Mecca, Saudi Arabia – US$15b
3. Resorts World Sentosa, Singapore – US$6.59b
4. Marina Bay Sands, Singapore – US$5.5b
5. The Cosmopolitan, Las Vegas, USA – US$3.9b
6. One World Trade Centre, Manhattan, USA – US$3.8b
7. Emirates Palace, Abu Dhabi, UAE – US$3b
8. Wynn Resort, Las Vegas, USA – US$2.7b
9. City of Dreams, Macau – US$2.4b
10. The Venetian Macao, Macau – US$2.4b
11. Princess Tower, Dubai, UAE – US$2.17b
12. Antilla, Mumbai, India – US$2b
13. The Palazzo, Las Vegas, USA – US$1.8b
14. Taipei 101, Taiwan – US$1.8b
15. Bellagio, Las Vegas, USA – US$1.6b
16. European Central Bank, Frankfurt, Germany – US$1.5b
17. Yankee Stadium, New York, USA – US$1.5b
18. Wembley Stadium, London, UK – US$1.5b
19. Burj Khalifa, Dubai, UAE – US$1.5b
20. Petronas Twin Towers, Kuala Lumpur – $US1.16b