The United Arab Emirates’s two major cities have a superlative rivalry. In Dubai, you will find the tallest building in the world, the first-ever seven-star hotel and the biggest indoor ski slope. Abu Dhabi has the world's most expensive hotel ever built and the first ever gold-dispensing ATM. For years, Dubai consistently bested its smaller sibling, but the city's debt crisis and its downfall has allowed Abu Dhabi to shine. It bailed Dubai out to the tune of $10 billion when its economy hit the buffers while selling itself as the region's cultural capital.

Abu Dhabi has spent billions of dollars to attract big names like Guggenheim and the Louvre but its grandest cultural gem lies just on the outskirts of the city: Sheikh Zayed Grand Mosque. Named after Sheikh Sultan bin Zayed bin Khalifa Al Nahyan, the founding father of the UAE, he is buried in a shrine next to the opulent mosque. Only the best resting place would be good enough for a leader who is revered by all the Emiratis as the man who oversaw the transition of the UAE from a poor desert country to an oil-rich Gulf state with all its trappings.

It is hard to get a full idea of the size of the mosque, the equivalent of five football fields, even as you drive along the road that links Abu Dhabi to Dubai. From afar, it looks so simple - a pure white wedding cake rising up from the desert. It is the colour that stands out: a milky white marble with gold atop the domes and a vast marble courtyard that blinds you in the midday sun. But it is at night that the mosque glows - its 82 domes light up like dozens of bright light bulbs in the dark sky.

If you turn up outside of prayer time, you can visit the mosque for free. Ladies have to don the traditional abaya - the loose black robe that is worn by women in the Gulf - and cover their hair. Expert Emirati tour guides will take you around the mosque and show you the prayer halls. And you can ask all the questions you have ever wanted to about Islam and the UAE. How many palm trees are in the UAE? Forty million. How many people can fit into the Sheikh Zayed mosque for prayer? More than 40,000.

But of course, being in the UAE, the mosque comes with superlatives. It has the world's largest hand-knotted carpet, crafted by 1,200 Iranian craftsmen. With 2,268,000 knots, the carpet is said to be worth $8.2 million. Take that, Dubai.

Katy Watson is a Dubai-based Middle East business reporter for BBC World News.