LONDON — Europe’s largest airport was welcoming a record number of passengers this morning as athletes, officials and media from all over the world began arriving for the London Olympics.

Heathrow says athletes from 50 nations will arrive in what it is describing as Britain’s biggest peacetime transport challenge. Some 236,955 passengers are expected to pass through the airport. The previous record of 233,562 was set in July 2011.

Heathrow has enlisted some 1,000 volunteers to meet and greet athletes, officials and media — hoping to put a bright face on the games. Special teams have been created to deal with oversize items such as javelins and bikes. Hundreds of immigration agents will be on the job to ease the long lines that have plagued the airport.

Rows of Olympic VIP buses will be waiting to whisk teams and coaches to the Athletes Village. Baggage teams in reclamation halls are dealing with larger items such as javelins and bikes.

“It’s about the people and about the relations.” said Nick Cole, who heads the airport’s Olympic operations. He noted that the staff were wearing their pink colored gear — hoping to stick out in a crowd. “We’re going to be on show on Monday,”

The airport usually handles 100,000 to 110,000 arrivals a day, but that will swell to 120,000 on Monday, many of them Olympic VIPs. Another big arrival day will be July 25, two days before the games’ opening ceremony.

There was also an increased police presence, including sniffer dogs, along with the volunteers and the regular Heathrow staff.

No unusual problems were reported early Monday, as athletes including members of the American sailing team, Jamaican swimmer Alia Atkinson and an Italian kayaker were among the early arrivals.

People arriving at Heathrow’s Terminal 4 said the immigration lines were not long.

Transport into central London was smoothed by the official opening of a “Games Lane” along the M-4 motorway. The special lane is open only to Olympic officials, VIPs and athletes.

More “Games Lanes” will open in other parts of London as the games approach.

The London Olympics start July 27 and end Aug. 12.