Ireland's boxing gold medal-winner Katie Taylor has boarded a flight from Heathrow on its way to Dublin Airport.
Staff at the UK’s biggest airport are dealing with the challenge of getting thousands of Olympic athletes away on their flights home.
Katie said she was looking forward to seeing her grandmother, Kathleen Cranley.
Shortly before boarding her flight, Taylor said: “My grandmother has just turned 80. I’m very keen to see her and the whole family again.
“The atmosphere when I fought was tremendous. It’s been an incredible Games and I have been privileged to be part of it.
“It’s all going to be a bit mad when I get home (to Bray in County Wicklow). I’m looking forward to celebrating.”
The Irish Sports Council has said there is no homecoming for Team Ireland today, because the athletes did not want it.
Ireland's Olympians arrive home at lunchtime bringing five medals with them, the biggest haul Ireland has managed in almost 60 years.
An event will take place to honour them in Dublin city on Wednesday outside the Mansion House.
However, separate events will be held in Mullingar, Bray and Belfast today to welcome back medal-winning boxers.
John Treacy, CEO of the Irish Sports Council and Olympic medallist, said the athletes decided to postpone the Dublin homecoming and that must be respected.
Mr Treacy said: "From what I hear the athletes decided they didn't want a homecoming, they just wanted to go home to their families and we have to listen and be sensitive to the athletes.
"What I would actually say to you is this, the atheletes have decided on this, I am not getting into this controversy, the athletes have decided on it and that's fine with us."
There will be around 116,000 people who will depart from Heathrow, making it one of the west London airport’s busiest-ever days.
This compares with around 95,000 who would be departing on a normal day and is not far behind the record of 123,000 departing passengers set on July 29 last year.
Around 6,000 athletes were able to check their bags through at the Olympic Village in east London last night. They will leave Heathrow today with around 9,000 other Olympics-related passengers.
The athletes will have their own specially-constructed Games terminal, which is the size of three Olympic swimming pools. It has 31 check-in desks and seven security lanes.
Athletes are expected to depart with more than three bags per person, including outsize sporting equipment.
They will arrive by coach and be treated to a special London-themed send-off, the details of which Heathrow operator BAA is keeping a closely-guarded secret.
No aircraft will depart from the Games terminal. Instead, athletes will take an airside coach to their final departure point where they will mingle with regular passengers as they wait for their flight.
Athletes will be clapped into each terminal by a guard of honour made up of Heathrow volunteers.
After three days of operation, the terminal will be decommissioned and the site returned to its original use as a staff car park.