A capacity crowd of 80,000 has gathered at the Olympic Park ahead of the opening ceremony of the Paralympic Games.
The Paralympics opening ceremony has begun with a spectacular display of dancing and a "big bang", watched by some 80,000 spectators.
Some 3,000 volunteers will take part in the event, which organisers have entitled Enlightenment.
Professor Stephen Hawking opened the event, speaking of the quest for understanding the universe.
Professor Stephen Hawking and actor Sir Ian McKellen will narrate the show, which is due to begin at 20:30 BST.
Some 3,000 volunteers are taking part in the show, which organisers have entitled Enlightenment.
There are still doubts the Paralympic flame will arrive on time, as the torch relay is running an hour late.
Meanwhile, there are doubts the Paralympic flame will arrive on time, after a delay.
The opening ceremony - which is being broadcast on Channel 4 and BBC Radio 5 live - signals the start of 11 days of competition by more than 4,000 athletes from 165 countries, including more than 300 athletes from ParalympicsGB.
The start of the show featured a flypast by Aerobility, a British charity that trains disabled people to become pilots.
Six Paralympians and former competitors then flew into the stadium on golden wheelchairs - Baroness Tanni Grey-Thompson was among them.
And the Queen has been welcomed by Sir Philip Craven, President of the International Paralympic Committee.
It is the first time she has officiated at the openings of both the Olympic and Paralympic Games.
The Union flag was carried in by representatives of the armed forces. Many Paralympians are drawn from service personnel.
Six-London based choirs - including the London Gay Men's Chorus and the Lewisham Choral Society - performed Principia, a specially composed piece by Greenwich based composer Errollyn Wallen.
Teams from all 165 countries are parading into the stadium in a section of the show which has been called Spirit in Motion by the directors. The process in total is expected to last 1hr 15 mins.
Music used for the parading athletes has been mixed and played by three London-based DJs - DJ Walde, DJ Excalibah and Goldierocks.
A Locog spokeswoman said they were still hopeful the torch being used in the relay would make it to the Olympic Stadium in time for the opening ceremony.
A Locog spokeswoman said they were still hopeful the torch being used in the relay would make it to the Olympic Stadium in time for the opening ceremony.
A back-up flame was earlier created at City Hall, to make certain the ceremony could start as planned.
A back-up flame was earlier created at City Hall, to make certain the ceremony could start as planned.
The opening ceremony - which will be broadcast on Channel 4 and BBC Radio 5 live - will signal the start of 11 days of competition by more than 4,000 athletes from 165 countries, including more than 300 athletes from ParalympicsGB.
'Journey of discovery'
Backstage, organisers and volunteers are busily applying final touches to props and paraphernalia - a wipe-down of a flag pole here, a lick of paint to a prop there.
The ceremony explores the twin themes of reason and rights, and we're promised a journey of discovery, led by celebrated scientist Professor Stephen Hawking and Shakespeare's character Miranda from The Tempest.
The cast includes 73 deaf and disabled professional performers and also well-known names like Sir Ian McKellen as a Prospero-type character, singer Beverley Knight and 3,250 volunteers aged 10-80 from all over the world.
Organisers say the show is about challenging perceptions. There will be athletes, flags, royals and Tom Heatherwick's cauldron as expected.
There will also be a Hadron collider and a fly-by by Aerobility - a charity that trains disabled people to become pilots - and the humble apple is also playing a key role in proceedings.
"You all need to make sure you have an apple," said artistic director Jenny Sealey ahead of the ceremony. "Because everybody, 62,000 people in the audience will also have their apple.
"We're asking people on television to make sure they have their apple. We want to stage the biggest ever apple bite."
Paralympic organisers are looking to break records before the Games have even begun!
A crowd of 80,000 people will watch the ceremony in Stratford, east London, which will be opened by the Queen and watched by the Duke and Duchess of Cambridge.
The start of the show will feature a flypast by Aerobility, a British charity that trains disabled people to become pilots.
Fifty specialist performers in the ceremony have taken part in an eight-week circus skills training programme in east London, and will take part in a high-wire act.
The show's two artistic directors have said the main themes of the ceremony will be empowerment and the challenging of perceptions of human possibility.
Prof Hawking - a world-renowned physicist who has motor neurone disease - will join Sir Ian McKellen to narrate a scientific "journey of discovery", inspired in part by Prof Hawking's own book A Brief History of Time.
The organisers have revealed that Prof Hawking will act as a guide to Miranda, a character from William Shakespeare's play The Tempest, through the show.
Sir Ian will play Prospero, another character from the play.
Co-artistic director Jenny Sealey said this evening's audience will be taken on an "exquisite journey of discovery inspired by the wonder of science".
She added: "Both Hawking and McKellen in their narrative talk about what we all need to remember: don't just look down at your feet, look at the stars, be curious."
She would not revealed the cost of the event, but said it had been put together on a "prudent budget".
The Paralympic torch began its journey in Stoke Mandeville, the spiritual home of the Paralympic Games, on Tuesday night.
It was carried by 580 torchbearers in total, and after being carried past some of London's most famous landmarks, is to be used to light a scaled-down version of the Olympic cauldron.
UK Sport and the British Paralympic Association have set a minimum target of 103 medals this time from at least 12 sports, including swimming, athletics and rowing.
Hopes are high that ParalympicsGB will emulate the success of TeamGB, but one of the UK's most decorated Paralympians has warned the competition for medals is likely to be tougher than ever.
Britain finished second in the medals table at the 2008 Games in Beijing, winning 42 golds, 29 silvers and 31 bronzes. China were top with 211 medals, of which 89 were gold.
Speaking before the ceremony, Prime Minister David Cameron said he believed the Games were "going to to make the whole country incredibly proud".
He told Channel 4 News: "The Olympic Games made us proud but I think this will make us prouder still because you are going to see an extraordinary display of sport.
"We can be very proud that more Paralympians are taking part in more sports, in more stadia, watched by more people than at any time in the past.
"It's been a sell-out and that is, I think, a great story for our country and it will inspire a lot of people and change people's views about disability and that is absolutely crucial."
Are you going to the opening ceremony? Or are you hosting, or going to, a Paralympic party? Are you a torch bearer? Please get in touch with us using the form below.
Are you going to the opening ceremony? Or are you hosting, or going to, a Paralympic party? Are you a torch bearer? Please get in touch with us using the form below.
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