Ian CollinsContemporary Art Norwich is set to run amok from July 11 to August 31 in venues all over the city and spilling on to the streets.Ian Collins

Time was when we used to have an arts festival in Norwich every third autumn, with a very narrow focus on classical music. Now there is a most excellent explosion of creativity all through the year - with a visual spectacular in the summer.

Just as the current Aldeburgh Festival fortnight is only the flagship for a fleet of multi-media events floating across 52 weeks of the calendar, so the spring Norfolk and Norwich Festival is a springboard for constant enterprise.

A much-expanded festive team now runs Creative Partnerships across the community throughout the year. And, having just taken us into the workplaces of 250 visual artists via Norfolk Open Studios, the art activists are now inviting everyone to the great big party that is Can - Contemporary Art Norwich.

Artistic director Jonathan Holloway says: 'I love Contemporary Art Norwich. It is where we get the chance to re-experience our worlds in a completely new way; where the humdrum becomes beautiful, moving or terrifying; where what is concealed breaks into our lives in the most unexpected ways.

'This region has long been known for the richness of its artistic talent and endeavour. Now the east of England is shaking up the visual art world with a new confidence and bringing together a brilliant breadth of work that you wouldn't see anywhere else.'

In July and August more than 100 emerging and established artists from all over the continent and planet, as well as from Norfolk itself, will be confirming our city as a leading centre of contemporary art, with challenging, amusing, amazing and confusing work to be shown in six venues as well as spilling on to the streets.

The Can Opener will be applied on Saturday, July 11, with a big celebratory bash at Norwich Arts Centre and the beginning of Fishing for Trout, a show of photographic tableaux on a theme of childhood escape into nature by the Saatchi-collected Norfolk-based artist Frances Kearney.

That launch day also sees the unveiling of A Norwich Beacon by the Office for Subversive Architecture - a monumental mock Gothic arch in Tombland - and the start of city-wide tour (to August 8) of Ivan and Heather Morison's Tales of Space and Time, a mobile library made from a former army fire engine and filled with works of science fiction.

The following Monday sees the opening of the highly influential East International 09 in a new biennial format at what is now the Norwich University College of the Arts (www.eastinternational.net).

As steered since 1991 by Lynda Morris and a shifting cast of curators, this evolving event has already placed the former school of art and design prominently on the international map for cutting-edge creativity. The abiding aim has been to counter any inward perspective of western Europe by exploring and interacting with art from the very diverse cultures within and beyond the old Soviet bloc.

This far into the eastward journey, Lynda says: 'It seems like hardly an exhibition takes place that does not have at least one East artist in it, whether it is the Turner Prize, the Tate Triennial or the Platform for Art. For a project sustained by a regional art school, now a university college, it has been a remarkable event.

'Successive waves of students have benefited from the experience, as have other arts organisations in the city. It means something in the world of contemporary art to come from Norwich.'

This year's East curators are Michael Baldwin and Mel Ramsden from Art & Language - the Coventry-originating but wide-ranging alliance of art, politics and philosophy helping to found Conceptual Art - and art historian Lukasz Gorczyca and poet Michal Kaczynski from Warsaw's Raster Gallery.

Lynda Morris comments: 'The breadth and contradictions they represent seem to parallel the complex and confusing array of positions and ideologies among younger contemporary artists across Europe.'

And so the 25 selected artists range from graphic political printer and poster-maker Adam Burton to Anna Okrasko whose 3,018 10x10cm graphite-covered canvases line the walls of a narrow corridor down which we are invited to walk without marking ourselves in the process.

With Andrzej Wajda's magnificent film, Katyn, now released in the UK, Poland's tragic history during the second world war is finally fully in the spotlight. Sculptor and film-maker Olaf Brzeski provides a fresh and shocking focus with a haunting movie called In Memory of Major Jozef Moneta in which soldiers hiding in forests are turning into animals in an even more beastly assembly than Angela Carter's The Company of Wolves.

At first glance, James Hopkins seems to be a maker of very uncomfortable furniture, with too few materials to hand, but his Love-Seat carries a message within its empty spaces.

Emptiness is even more apparent in the Snow Black display of 'invisible art' by several artists staged by Agnieszka Kurant. Some pieces are visible only at night; others only in daylight. Some don't yet exist; others are already extinct.

And that's just a small sample of East International 09's dazzling (and dizzying) variety.

The Sainsbury Centre for Visual Arts has already opened its Can-linked exhibitions The Art and Theatre of Tadeusz Kantor and Take a Look At Me Now: Contemporary Art from Poland, with events around the shows still to come (visit www.scva.ac.uk for details).

Under way also is a rolling programme of solo shows - Lynn Hynd (to June 21), Jamie Shovlin (July 2-21) and Matthew Darbyshire (August 2-21) - at Outpost Gallery (www.norwichoutpost.org), with a series of short Outhouse residences elsewhere in Norwich for 21 British and European artist starting next month.

July 18 sees Norwich Castle Museum and Art Gallery joining the party with No Visible Means of Escape: Contemporary Art and Imprisonment (www.museums. norfolk.gov.uk) - an exhibition of detention, punishment and surveillance as deep as a dungeon and far broader than a cell set against the cultural centre's history as a fearsome jail.

The arresting Castle exhibition takes its name from the Marc Quinn sculpture of a suspended cast of the artist's own body which also forms a focal point for the exhibition.

Talking of surveillance, Photo-ID - an exhibition of work by 10 internationally-noted talents to be curated by Norfolk Contemporary Art Society at The Forum August 1-29 - considers the implications of recent research into the human genome and how its variations affect the way we think about identity.

And there's a really wild weekend in store for the Cultural Olympiad Open Weekend (July 24-26). In London Street, from 9pm each evening, the Argentinian artist Mariano Pensotti will present La Marea - secret stories and private emotions revealed in nine fictional scenes played out in shop windows and on street corners… with the actors' thoughts shared via projected subtitles.

And on that Saturday evening (July 25), Richard Dedomenici will curate Rub Me Up the Wrong Way 2 - a medley and a melee at Norwich Arts Centre featuring international live art and provocative bands from The Panacea Society to Foreign Muck.

Contemporary Art Norwich 2009 runs amok from July 11 to August 31. For a free programme, e-mail can@nnfestival.org.uk