The V&A and Tate have been running regular "lates" – staying open beyond normal museum hours for some time. Now, for one weekend only, more than 130 museums, galleries and heritage sights around the country are joining in, as part of the Museums at Night initiative.
This weekend, in Wales, Bodelwyddan Castle is holding a spooky sleepover complete with haunted family treasure hunt and a torchlit ghost walk; in Bath there will be late-night tours of the historic Roman Baths and in Bristol, people will be able to take the first ever night-time tour of the illuminated Clifton Suspension Bridge.
Culture 24, a non-profit organisation which promotes culture online is co-ordinating the events. Director Jane Finnis believes it's a great way to attract new audiences. "It gets venues thinking about how they can do something different." In Exeter this means artist Simon Pope giving a one-off tour of the cathedral at dusk, while in Newcastle, the whole town is getting involved in a Culture Crawl.
And in London, John Cale (ex-Velvet Underground) will be discussing music, art and his plans for the Venice Biennale at the National Gallery; there will be candlelit tours at Sir John Soane's museum and 1940s dancing aboard HMS Belfast.