Former miners act as guides for tourists at Big Pit

Big Pit at Blaenavon, south Wales, is among the final four museums competing for the UK's richest arts prize.

Also in the final are the Museum of Great Yarmouth Life, Coventry Transport Museum and County Durham's National Railway Museum.

Big Pit will find out if it has won on 26 May.

All four finalists, which came from an initial shortlist of 10, focus on the UK's industrial heritage.

To be shown round 300ft below ground by somebody who was a miner was one of the top 20 experiences of my life Prize judge Victoria Hislop

A former working mine which closed in 1980, Big Pit was nominated following renovation work worth �7.1m.

It pulled in a record 141,000 visitors in 2004, up from 112,000 in 2003.

Mine manager Peter Walker said: "It's like being nominated for an Oscar.

"We've got the museum professionals telling us what the public have been telling us for the past year - that we've done a good job with the redevelopment.

"Visitor numbers have increased dramatically and this year we've started off with a record month for February and it looks like being a record month for March."

The pit has converted into a museum since closing in 1980

At the height of its working life a century ago, Big Pit - also now known as the National Mining Museum of Wales - employed 1,300 miners.

Even before its revamp, the museum had tried to make visitors' experience interactive, allowing them to descend 300 feet down a mine shaft accompanied by former miners who now act as guides.

The museum attempts to recreate the authentic experience of a south Wales coal mine and has preserved the pithead baths as well as the journey to the underground coalface.

Mr Walker added: "The biggest critics we have to satisfy are our own workforce because everybody's worked in the (mining) industry before."

One of the Gulbenkian Prize judges, journalist and novelist Victoria Hislop, said Big Pit was a "totally authentic" underground experience.

She added: "There's nothing added or changed in that pit - it's absolutely as it is.