LONDON, England (AFP) — Athletes and Olympics visitors descended on London today in the first wave of arrivals for the Games, bumping up traffic through the capital's busy Heathrow airport to record levels.

Around 1,000 members of the so-called "Olympic family", including 350 athletes, were due to fly into Heathrow on the first day of arrivals, as a brigade of cheerful volunteers swung into action to welcome them.

In total almost 237,000 passengers were set to pass through the airport on the western edge of the British capital, compared to 190,000 on an ordinary day, officials said.

"We are expecting people from over 50 nations today," said Tom Willis, operations director for Heathrow's Terminal 4.

"We have spent £20 million getting ready to welcome the world to Heathrow.

"Part of that has been training and recruiting 1,000 Games volunteers from the local community, so visitors will be met by a brightly-coloured, pink-uniformed volunteer who will welcome them to London."

Volunteer Michael Martin, 34, dressed in a bright pink t-shirt as promised, was waiting eagerly at Heathrow to greet athletes arriving ahead of the Games which open on July 27.

"Being part of the Olympics is a great honour and privilege for me," said Martin, who is taking time out of his job as a self-employed architect to work unpaid at the airport.

The US sailing team and Italy's canoeists were among the first to touch down at Terminal 4, followed by members of the Dutch beach volleyball team.

"We are meeting and greeting athletes and higher ranking officials as they get off the plane and we support them through customs," added Martin, one of a band of volunteers who speak 20 languages between them.

"I am hoping to meet some athletes later this afternoon. It's great!"

Despite weeks of apprehension in Britain over mounting queues at passport control at the world's busiest international airport in terms of passenger traffic, the first Olympic arrivals appeared to have few complaints.

The Dutch female beach volleyball players who flew in from Amsterdam wearing their vibrant orange kit said their passage through customs was seamless.

"From the moment we walked off the plane there were people helping us straight away. It is very well organised," said team member Marleen van Iersel.

The blonde 24-year-old, who will be competing in her first Olympics when she joins other teams on London's Horse Guards Parade, said the moment she had waited years for is finally in sight.

"We have been working towards this for four years now so we're very excited," she said, smiling broadly.

Armed police and sniffer dogs were part of the welcome party, but airport bosses played down their presence.

"Security is always a priority at Heathrow," said Willis. "It is business as usual with security, which means it is really very secure and no stone is left unturned."

After stepping off the plane, athletes are being whisked to the Olympic village in Stratford, east London, which will become their home from home for the next month.

Yesterday's arrivals were only the first test for London's infrastructure, with thousands more due in the coming days.