Brunel's ss Great Britain in Bristol; The Collection - Lincoln's museum of art and archaeology; the Underground Gallery at the Yorkshire Sculpture Park in Wakefield; and the modernised galleries for the medical collection at the Hunterian Museum in London are now competing for the £100,000 prize and the kudos that goes with it. The winner will be announced on 25 May.

'We're absolutely thrilled,' Matthew Tanner, the director of the ss Great Britain Trust, told Museums Journal. 'It has taken us since 1997 to get from the embryonic stage to completion in July 2005.' The project cost £11.3m.

Tanner said that Brunel's 1843 pioneering ocean liner, was an icon and should be treated like a crown jewel. 'We had to come up with a method for preserving a 3,000-tonne ship in a wet and boggy dry dock without restricting public access. The glass sea with its controlled climate was the solution, and the ship has the same amount of iron as when we started.'

Lincoln's new museum is a mix of ancient artefacts, from the Stone Age through to medieval times. The Collection opened in October last year and has already had an exhibition curated by Turner prize-winning sculptor Grayson Perry.

'We're delighted to be one of the four,' said Will Mason, the commercial manager of the Collection. 'Visitor reaction has been very, very good and it's a lovely accolade.'

The Yorkshire Sculpture Park commissioned its Underground Gallery in April 2003. Completed in December 2004 at a cost of £2.75m, it is one of the largest purpose-built galleries constructed in Britain for several years.

Meanwhile, the Hunterian Museum has undergone a £3.2m refurbishment to make its renowned collection of anatomy and pathology specimens more accessible.

The annual Gulbenkian Prize is open to museums and galleries in the UK. 'It has been very difficult to choose,' said Diane Lees, the director of the V&A Museum of Childhood, and a member of the judging panel. 'All of the four shortlisted were the most successful at tackling their individual problems.'

Deirdre Mason