Currently under construction in Dubai, Hydropolis is the world's first luxury underwater hotel. It will include three elements: the land station, where guests will be welcomed, the connecting tunnel, which will transport people by train to the main area of the hotel, and the 220 suites within the submarine leisure complex. It is one of the largest contemporary construction projects in the world, covering an area of 260 hectares, about the size of London's Hyde Park.

"Hydropolis is not a project; it's a passion," enthuses Joachim Hauser, the developer and designer of the hotel. His futuristic vision is about to take shape 20m below the surface of the Arabian Gulf, just off the Jumeirah Beach coastline in Dubai. The £300 million, 220-suite hotel is due to open at the end of 2007 and will incorporate a host of innovations that will take it far beyond the original blueprint for an underwater complex worthy of Jules Verne.

There are only a few locations in the world where such a grandiose dream could be realised. A high proportion of today's architectural marvels are materialising like fanciful mirages from the desert sands. We have come to expect extravagant enterprises to be mounted in the Middle East, and especially in Dubai. "This venture could only be born here in Dubai," says Hauser. "It [has] a very open-minded, international community - and that's what makes it so special."

The land on which Hydropolis is being built belongs to His Highness General Sheikh Mohammed Bin Rashid Al Maktoum, Crown Prince of Dubai. It was his last free beach property on this stretch of coast. The project is a fantastic one, yet Sheikh Mohammed's success record with comparable schemes instills confidence that science fiction can become fact. With his support, several companies have been formed to kick-start this phenomenal project, and around 150 firms are currently involved. "There have been many visions of colonising the sea - Jules Verne, Jean Gusto and several Japanese architects - but no one has ever managed to realise this dream," says Hauser. "That was the most challenging factor, and that's what makes it so fascinating. Despite being a dream of mankind for centuries, nobody has ever been able to make living underwater possible."