You have to hand it to the London 2012 Festival team. When they call it "a once in a lifetime experience", I rather think they mean it. In an "age of austerity", this almighty splurge is not to be sniffed at. More than 25,000 performers and 12,000 events are involved, with every corner of the country, more or less, becoming part of it. Heaps of it is free at the point of use. And if the full programme is... well, a little confusing, perhaps it could scarcely be otherwise, given the sheer scale of the bonanza.
The effort, really, is to please all the people for as much of the time as humanly possible. Imagine all the box-ticking. Cheap or free tickets. Youth. Britishness. Internationalism. Multiculturalism. Inclusiveness. Diversity. Kiddies. Education. Olympics. Paralympics. Contemporary arts. Heritage. Traditional arts. Pop culture. Classical music. Contemporary music. Dance. Comedy. Theatre. Installations. Fashion. Shakespeare. More youth. Still more youth. The amazing thing is that they seem to be pulling it off.
It's not without its problems, though – not least in defining its own identity. What's the difference between the London 2012 Festival and the Cultural Olympiad? Well, the latter began four years ago and the London 2012 Festival "officially" starts on 21 June, with four huge events in different places. But many of the events included in the London 2012 Festival, like the Globe to Globe productions of Shakespeare in many languages, have already been going on for months. Of the opening night's events, The Big Concert, in Raploch, is being televised on BBC4 – but it's odd that, inspiring as Gustavo Dudamel and his Venezuelan orchestra undoubtedly are, and the transformative musical education they symbolise, this event actually has nothing to do with London, or the Olympics, or the year.
It gets more muddling still. The biggest classical music component of the festival is The Proms, in its entirety – which of course is already a festival in its own right. The World Shakespeare Festival, too, has an identity and a length all its own. I tried to make a Venn diagram to demonstrate which festival is part of which other one and to what degree, and which big series is entirely contained within which bigger shebang which was pre-planned, but it started to resemble a psychedelic drawing of Mickey Mouse.
Isn't it a cop-out simply to trumpet pre-existing events as if they're a special one-off? In certain ways this risks looking like a missed opportunity on a massive scale. And if there is indeed a serious missed opportunity, it's the lack of presentational clarity that maybe results from trying to be all things to all people. Still, there's realpolitik at work. Why set up a classical series to compete with the Proms, which are such a popular fixture and already emblematic of London in summer? If you can't beat 'em, incorporate 'em. They're a subset, then, of an embarrassment of riches.
What's truly distinctive about the festival, and the thing that unifies it – well, almost – is the way it celebrates its settings. Try the marvellous concentration of multimedia installations and genre-bending events. Walk up Arthur's Seat from Edinburgh carrying a light and you can be part of one; listen out for what the wind can do to a cello on the Portland coastal path in Devon; explore ancient myths in the forests of Wales or watch acrobatics and pyrotechnics over Lake Windermere as the Olympic torch trundles into Cumbria.
It's not only these relatively wacky happenings that are rooted in their spaces: so, too, are many of the more traditional performances. The Big Concert sees Dudamel – himself perhaps classical music's equivalent of an Olympic torch – performing alongside the children of Raploch, whose progress in Sistema Scotland more than deserves this celebration. In Suffolk, the Aldeburgh World Orchestra is not only a brand-new international youth ensemble under the baton of Sir Mark Elder; it's also a very public symbol of what the coastal town, inextricably associated with the great composer Benjamin Britten and his legacy, does so well towards the musical education of gifted youngsters.
And because of the location-rich aspects of the festival, you ignore it at your peril: if you don't find it, the chances are that at some point it will find you. "Pop-up" events are very much the flavour of the summer. An American dance company promises hair-raising virtuoso feats around London's prime sites. A train full of African musicians is coming to a station near you; a barge full of comedians is travelling the country's canals.
The best news is that, behind the fuzzy subsets and that clumpy Olympic logo, Britain has been thinking big about its arts scene. This is a giant effort. Let's hope that the outcome is good enough to justify its cost; and that it does all it should to draw people together and lift the spirits.
The top 20 events in the London 2012 Festival
The Big Concert
Old School Field, Raploch, Stirling
Gustavo Dudamel and the Simon Bolivar Orchestra join 450 children from Big Noise Raploch (Sistema Scotland) in an outdoor event celebrating the transformation of lives through music.
Yoko Ono: To the Light
Serpentine Gallery, London
A major retrospective of the conceptual artist, including her new large-scale project, Smile.
19 June-9 September
Symphony Hall, Birmingham
A new grand-scale choral work by the composer Jonathan Harvey. Edward Gardner conducts the CBSO and choirs.
BBC Radio 1's Hackney Weekend
Hackney Marshes, London
The biggest outdoor event ever staged by BBC Radio 1 brings to Hackney some of pop's biggest names: Jay-Z, Rihanna, Ed Sheeran, Plan B and more. Free, but ticketed.
Secret location, Wales
National Theatre Wales has reimagined Shakespeare's Coriolanus for the era of multimedia, celebrity culture and 24-hour news.
Aldeburgh World Orchestra
Snape Maltings, Aldeburgh, Suffolk
A new international orchestra of 124 top-level young musicians conducted by Sir Mark Elder performs music by Mahler and Shostakovich.
20 & 22 July
BT River of Music
Music on the Thames, with six stages carrying the music of a different continent. Stars include Wynton Marsalis, Baaba Maal and Angelique Kidjo.
Various coastal locations
Love-poetry installations at beauty spots around the British coast, masterminded by Fiona Shaw and Deborah Warner.
Tracey Emin: She Lay Down Deep Beneath the Skin
Turner Contemporary, Margate
This free exhibition is the first of the artist's to be held in her home town. Work by Rodin and Turner also features.
To 23 September
Land of the Giants
Titanic Slipways, Belfast
Northern Ireland's largest outdoor arts event promises "a unique tale on an epic scale", with a cast and crew of 500. Expect myth, history, fireworks, acrobatics, music, and more.
A train carrying top African and European musicians led by Damon Albarn travels the UK, stopping to give impromptu performances in unexpected places.
Stockhausen: Mittwoch aus Licht
Argyle Works, Birmingham
World premiere by Birmingham Opera of the late Karlheinz Stockhausen's opera, in a former warehouse, with 160 performers, including music streamed from helicopters.
Mike Leigh: A Running Jump
Hackney Picturehouse, London
Taxis and dodgy second-hand cars feature in Leigh's newly created film reflecting on sport in everyday life.
Circa & I Fagiolini: How Like an Angel
Norwich, Ely, Gloucester & Ripon cathedrals
Aerial circus skills from the Australian troupe Circa together with live sacred music from the choir I Fagiolini, touring to four great cathedrals in succession.
26 June-19 July
Anish Kapoor: Orbit
Olympic Park, London
The Turner Prize-winning artist's twisting red tower next to the Olympic Stadium is, at 376ft, the tallest sculpture in the UK.
Big Street Dance Day
Invitation to the dance for all in the country's streets, squares and parks. Trafalgar Square hosts choreographer Wayne McGregor with 2,000 dancers.
South West Coast Path, Portland, Dorset
Composer Pierre Sauvageot is assembling 500 musical instruments to be played by the wind. It forms "a symphonic soundscape, unique to each visitor".
31 August – 9 September
Tall Tales from the Riverbank – Comedy Barge
Various canal locations
A bargeload of comedians travels the UK, stopping off for gigs and finishing at the Edinburgh Festival.
1 July – 27 August
Gilberto Gil is joined by the London Symphony Orchestra, while Sir Simon Rattle conducts the UK premiere of Wynton Marsalis' Swing Symphony.
4 July & 25-26 July
NVA – Speed of Light
Arthur's Seat, Edinburgh
A choreographed walk/run with audience members carrying lights, illuminating Edinburgh's famous natural landmark. Each performance will be entirely different, depending on the weather and who turns up.
9 August-1 September