Monumental poll returns to save crumbling masterpieces

It is the competition where a workhouse is as likely a winner as a castle for a king. Restoration, the BBC series that raised millions of pounds last year to rescue a piece of crumbling heritage, returns next month with a new list of historic sites bidding to be saved.

From the UK's last remaining open-pan salt works, near Northwich in Cheshire, to the world's first radar station at Bawdsey in Suffolk, 21 architectural gems will be battling to win the public's affection.

A final vote later in the summer will decide which of them receives a cash windfall raised from various sources, including the telephone voting lines.

Last year's winner, the Victoria Baths in Manchester, was given £3.5m thanks to 2.3 million calls and a grant from the Heritage Lottery Fund.

Griff Rhys Jones, the comedian, heritage campaigner and Restoration presenter, said the first BBC 2 series had been an "enormous success", attracting nearly three million viewers.

He said: "People from completely different walks of life watched it, paid attention and voted. Lots of people were saying things like, 'My husband has never, ever voted for anything on television before, but he insisted that we vote on this'."

This year's shortlist is an eclectic mix of the architectural history.

The Llanfyllin workhouse in Powys, mid Wales, is a Grade II-listed building from 1838. A lock-keeper's cottage in Newforge, Belfast, is the last remaining in public ownership on the Lagan navigation canal.

Cardigan Castle in west Wales is where Henry VII stayed during his march to the Battle of Bosworth Field in 1485 and Sheffield Manor Lodge in Sheffield is where Mary Queen of Scots was held for 14 years.

One of the most dramatic contenders is Strawberry Hill at Twickenham, Middlesex, which is so important to architectural history it appears on the World Monuments Fund watch-list of most endangered sites. It is a Gothic villa designed by Horace Walpole, the son of Britain's first prime minister, which helped inspire the Gothic revival.

Sherborne House in Sherborne, Dorset, is a Palladian palace which was the country retreat of the 19th-century Shakespearean actor Charles William Macready, who once had Charles Dickens as an overnight guest.

The South Caradon mine in Bodmin was one of Cornwall's largest copper mines with 38 miles of underground tunnels until its closure in 1890 since when it has been virtually untouched.

And another contender from the West Country will be Castle House in Bridgwater, Somerset, a rare surviving example of an early concrete house. It was built in 1851 by a local brick-maker.

The series stars on 8 May, with detailed programmes broadcast from July.

Restoration was warmly welcomed last year by heritage organisations who are alarmed at the state of Britain's built heritage. The UK has lost a building or monument every day since the end of the Second World War.

Portencross Castle, Portencross, Ayrshire

Where Robert Stewart, the grandson of Robert the Bruce, is thought to have stopped as he travelled to be crowned Robert II of Scotland, the first Stewart king. Now on the verge of collapse

Armagh Gaol, Co Armagh

Northern Ireland's oldest prison, it was built between 1780 and 1852 and regarded as "one of the most advanced houses of detention in the kingdom". Closed in 1986, it is Grade A-listed

Newstead Abbey, Ravenshead, Nottinghamshire

Best known as the ancestral home of the poet Lord Byron, who featured it as "Norman Abbey" in his epic Don Juan.Originally an Augustinian priory founded by Henry II in about 1165

Old Grammar School and Saracens Head, Kings Norton, Birmingham

Kings Norton is dominated by tower blocks, but has a number of historic buildings, including a 15th-century timber-framed school

THE 21 BUILDINGS

Portencross Castle, Ayrshire

Knockando Wool Mill, Morayshire

Hall of Clestrain, Orkney

Lock-Keeper's Cottage, Belfast

Armagh Gaol, Armagh

The Playhouse, Londonderry

Cardigan Castle, Cardigan

Llanfyllin Workhouse, Powys

Workingman's Institute & Memorial Hall, Newbridge

The Lion Salt Works, Cheshire

Gayle Mill, Gayle

Sheffield Manor Lodge, Sheffield

Newstead Abbey, Nottinghamshire

Bawdsey Transmitter Block, Bawdsey

Old Grammar School & Saracen's Head, Kings Norton

Strawberry Hill, Twickenham

Severndroog Castle, Greenwich

Archbishop's Palace, Charing

Castle House, Somerset

South Cardon Mine, Bodmin, Cornwall

Sherborne House in Dorset