Swimming enthusiasts from the ages of 12 to 78 took part in the 1.5 kilometre (0.9 mile) Victoria Harbour race which returned last year after a

33-year suspension.

Swimmers dashed between the eastern points of the Kowloon peninsula and Hong Kong Island against a stunning backdrop of towering skyscrapers and sharp peaks, replacing the normal harbour traffic of ferries and cargo boats.

"For over 70 years, the cross harbour races served as one of Hong Kong's most celebrated events," the organisers Hong Kong Amateur Swimming Association (HKASA) told AFP.

"The harbour race is indeed the city's most iconic sporting event," the HKASA added, pointing out that the response this year was "overwhelming".

The annual race, which was revived in 2011 due to popular demand, is a tradition which attracted hundreds of swimmers and thousands of spectators dating back to 1906.

The event was halted in 1978 due to a deterioration in water quality, but HKASA said they did not receive any complaints about pollution from the 1,000 competitors of last year's race.

"We have been monitoring closely the water quality based on latest information supplied by the Environmental Protection Department," it said.

Organisers added that the route was cleaned before the competition started.

Hong Kong is one of the world's busiest ports, with more than 425,000 vessels arriving and departing in 2010, according to official figures.