London's main airport is braced for its busiest day ever as the UK's creaking transport infrastructure prepares to take the strain of the 2012 Olympic Games.
Heathrow's meet-and-greet army charges into action for Olympics visitors
It is Britain's "biggest peacetime transport challenge", says the man in charge.
As the head of BAA's Olympic and Paralympic Games planning, Nick Cole has dedicated the past seven years to meeting that challenge.
The official host airport for the Games, Heathrow, has already processed thousands of members of the vast Olympic family.
But yesterday was Heathrow's busiest day on record, with an estimated 237,000 passengers processed.
The previous record, set last July, was 233,562, while on an average day 190,000 passengers arrive and depart at Heathrow.
Eighty per cent of all visitors to the Games will pass through Heathrow and more than 30,000 of them will be members of the Olympic family.
Athletes, coaches, managers, sponsors, 150 heads of state, VIPs and the world's media: their first impression of London 2012 will be made at Heathrow arrivals.
Mr Cole called it "a unique operation task and a massive challenge".
"The airport is one of the most popular international airports in the world and already operates close to capacity. Every part of the airport is working together to ensure we can give the athletes a warm welcome and ensure all passengers enjoy the atmosphere."
Mr Cole and his team travelled to former host cities Vancouver, Beijing and Sydney in the planning process.
The Olympic plans have cost the British Airports Authority more than £20 million (Dh114m).
The airport has installed 1000 ramps, six powered stair-climbers, 12 ambilifts that carry passengers and wheelchairs from ramp to aircraft, and 13 scissor lifts in anticipation of the 7,000 paralympians.
Two hundred extra staff have been recruited to accommodate four times the usual weekly number of wheelchair users - 1,800 in total.
Dedicated arrival lanes, known by airport workers as the "Pink Path" for obvious reasons, and immigration desks have been set aside to speed up the process between gate and Olympic Village.
Every hour six buses leave Heathrow's Terminals 4 and 5, carrying accredited Olympians to the village.
A thousand volunteers have signed up to meet and welcome the Olympic family, while their team leaders are among a dedicated team of 50 full-time staff preparing Heathrow for the Games.
Jenny Povey, 66, and her husband Peter, 65, volunteered to be Olympic welcomers.
"I saw they were looking for volunteers and thought it would be something my husband would like to do," Mrs Povey said.
"He used to work for British Airways in cabin service so he knows the airport. I thought it would get him out of the house and he went and signed me up too."
After three days of training they received their pink T-shirts and passes, and signed up for their first shift.
"I'm proud of my country and I want it to work well," Mrs Povey said.
Team leader John Sheratt, 37, has worked for BAA for 12 years. It is his responsibility to send volunteers to gates, working from flight schedules and mandates listing the number of athletes, VIPs and officials on board.
"It's one volunteer to every five Olympians," Mr Sheratt said. "We get about 10 minutes warning before a flight's actually about to land.
"Some of the gates are quite a way away so there's a lot of power-walking volunteers airside.
"They'll meet the arrivals at the gate, take them through immigration and show them down to baggage collection, even on to the Tube if that's what they need."
Heathrow's baggage system will have to deal with 13,000 more bags than it is designed for, so Olympians and non-Games travellers alike should breathe a deep sigh of relief when reunited with their luggage.
By the time the whole show is over, 500,000 passengers will have travelled through Heathrow.
Meanwhile, yesterday's record is unlikely to stand for very long. On August 13, 65 per cent of the Olympic visitors will depart. The airport will open a temporary Olympic terminal that day.
Built at Terminal 4, and with 31 check-in desks to deal with the mass departure, it will stay open until August 15.