The Sands SkyPark in Singapore is an awe-inspiring engineering wonder. This unique structural masterpiece, designed by visionary architect Moshe Safdie, floats atop the three soaring Marina Bay Sands hotel towers 200m in the sky. At the top of the 55 storey building is a 150-meter infinity swimming pool.

But swimming to the edge won't be quite as risky as it looks. While the water in the infinity pool seems to end in a sheer drop, it actually spills into a catchment area where it is pumped back into the main pool. The pools have two circulation systems. The first functions like that of a regular pool, filtering and heating the water in the main pool. The second filters the water in the catch basin and returns it to the upper pool.

The infinity pool on the roof of SkyPark spans the three towers of the hotel. The platform itself is longer than the Eiffel tower laid down and is one of the largest of its kind in the world. At three times the length of an Olympic pool and 650ft up, it is the largest outdoor pool in the world at that height.

The hotel, which has 2,560 rooms costing from £350 a night, was officially opened last week with a concert by Diana Ross. The £4billion hotel makes it the world's most expensive hotel.