The gallery's opening was delayed because of security issues

The Middlesbrough Institute of Modern Art (Mima) was proposed following the success of Gateshead's Baltic complex.

Construction of the �19m complex started in July 2004, but a planned opening for 2006 was delayed because of environmental and security issues.

Mima has eight exhibition spaces, an education suite, auditorium and conservation studio.

Mima director Godfrey Worsdale said: "The gallery and the new public square have cost approaching �20m, but people need to remember that we have attracted inward investment in excess of �15m.

'Great thing'

"Mima is opening today, but it is not just here for today, it is going to be here decades and centuries so our grandchildren and their children will still be coming through the doors to see fantastic art."

Designed by Dutch architects Erick van Egeraat Associated, the gallery's first exhibition includes works from Picasso, Matisse, Andy Warhol and Damien Hirst.

Mr Worsdale added: "I think this is a great thing for the start of a new millennium that Middlesbrough has this to look forward to for generations.

A huge firework display will cement the gallery's opening on Saturday evening.

The modern and contemporary art collection comprises more than 1,000 paintings, drawings, prints, photographs and sculpture which include works by Ben Nicholson, David Bomberg, LS Lowry, Stanley Spencer, Gwen John, David Hockney and Bridget Riley.

A contemporary international jewellery collection consists of both precious and non-precious jewellery. Examples from the collection have been featured in many major publications on the subject and have toured widely.

The 20th century British ceramics collection is claimed to be one of the most important of its kind in the country, charting the studio ceramics movement from the 1920s to the present day.