Today's (June 23) grand regal opening, will mark another historic moment for Heathrow airport at The Queen's Terminal which has been named in honour of the monarch.

The Royal celebratory event includes a tour of the airport's flagship £2.5bn building as well as a plaque unveiling for The Queen who will be accompanied by the Duke of Edinburgh, this afternoon.

Heathrow revealed an invitation was sent to Buckingham Palace, and was accepted two months ago, on April 23.

Heathrow Airport, Her Majesty The Queen visitis the airport, 1970s. The old Queen's building at Heathrow.

The old Terminal 2 was opened by The Queen in 1955, near the start of her reign.

Originally called the Europa building and built to deal with 1.2 million passengers a year, by the time it closed in 2009, the terminal was handling eight million passengers - five times more.

The terminal provided 54 years of service before it was demolished to pave the way for a completely new building, now capable of handling 20 million passengers a year.

The new Terminal 2 dubbed The Queen's Terminal has taken five years to complete and will be home to 23 Star Alliance airlines as well as Aer Lingus, Virgin Atlantic Little Red and Germanwings carriers.

A new covered court connects the main transport links to the terminal, and the building has a three wave steel frame roof which also floods the building with natural daylight.

On arrival at Terminal 2 passengers can see their loved ones off with a clear view of the runway.

Live coverage of the official opening on Monday (23) so follow me on Twitter @SalinaPatel1

View The Queen's Heathrow visits to Heathrow since 1955.

See the transformation from the old Terminal 2 to the new Queen's Terminal.

T2 - THE FACTS:

£2.5 billion makes T2 one of the UK's largest privately funded construction projects

35,000 jobs as part of T2's construction

Six months of trials - including 4,000 bags per hour tested

26 airlines will move into T2 over six months

14,000 volunteers helped test T2 during more than 180 trials

1,700 training sessions delivered to prepare the T2 team

16 million passengers a year - capacity of 20 million

28 gates

Eight A380 piers

33 shops

17 restaurants

36 immigration lanes plus 10 e-gates

29 security lanes

634 toilets

42 drinking water fountains

7,106 seats

1,340 car parking spaces

60 check-in kiosks

66 self-service kiosks

99% of materials from the old T2 recycled or reused