Institutions from Cornwall to Newcastle are organising events and special exhibitions for the occasion. The theme for 2007, People - Who Are We?, encourages museums to look at identity.

This is particularly relevant in a year when Britain's role in the slave trade has come under the spotlight and when there is so much in the media about immigration.

'There is great participation by the national museums this year,' said Ylva French, the director of the Campaign for Museums, which runs the event. 'It's good because they lead the sector and help create media awareness and set a good example for others. There has been great support from the regional hub structures as well.'

Themed events include workshops on how to trace your ancestors using the national prison archives at the NCCL Galleries of Justice in Nottingham; a Chinese documentary on migration at Bath's Museum of East Asian Art; and at the Science Museum in London there is the chance to see how our understanding of what it is to be human has changed.

The Night of the Museums will see doors stay open for special evening events. There will be storytelling, live music, and special screenings of the Night at the Museum film. This is part of a European-wide event that links in with International Museums Day on 18 May.

The NCCL will be offering an evening tour of its Victorian prison, which still contains medieval cells. Ellen Ward, NCCL's marketing and fundraising officer, said: 'The whole museum is a lot creepier at night. Visitors will get a different, altogether darker tour than usual.'

The Horniman Museum in London is offering two late-night events for adults. Firstly, its keeper of musical instruments will be giving visitors a sneak twilight preview of a major upcoming exhibition in the museum's music gallery.

Then there will be music of a different sort as the aquarium opens for one night to allow visitors to see and hear the museum's nocturnal dwellers come to life. Some of the frogs have been known to burst into song at night.

In Wales, Minera Lead Mines offers young people a chance to experience what it would have been like to go down the pit. The Ruthin Gaol in Denbigh will hold workshops based on the records and stories of the women incarcerated there.

In Scotland, Kelvingrove's statues will magically come alive; visitors will be locked away in a 17th-century gaol in Aberdeen; and like-minded singles can hook up at the National Gallery of Scotland. These events from 4-7 May are part of Show Scotland, the MGM's equivalent north of the border.

For details on Museums and Galleries Month events, visit: www.mgm.org.uk, www.showscotland.com

Aaron Davies