But it houses one of the most extraordinary architectural relics of the Second World War: a Baroque church interior built from bits of ration boxes and bully-beef tins by Italian prisoners of war in their camp in west Wales.
The 1,000 prisoners, captured in the North African desert campaigns, were shipped to Camp 70 outside the village of Henllan, in Dyfed, and put to work on the land. Here, in 1943, they sacrificed one of their flimsy sleeping huts and converted it into a Roman Catholic church.
Inside, after years of restoration work by Bob Thomson, 72, a Second World War veteran and owner of the POW camp site, the chapel has survived (just) as a memorial to the ingenuity of its builders, soldiers whose devotion matched that of the Renaissance craftsmen who built the great churches of Rome.
The chapel is dominated by a domed altarpiece. It is made partly of brick and partly - like the altar rail and the font - of concrete poured into moulds and painted to resemble marble. Concrete pillars are surmounted by scrolls forged from strips of bully-beef tin. The altar is decorated with 20 candlesticks, forged out of metal into silhouettes resembling ornate silver.
Ration boxes were used to build side chapels, a lectern and rounded interior frames for the square metalled window frames. Hanging above the door, on the inside, is an inscription, painted on a metal sheet: 'Questa e la casa di dio e la porta del cielo' ('This is the house of God and the door to heaven.')
Delicate arches across the nave were dressed with Aberthaw Cement sacks and painted over with elaborate Baroque images. The altar is dominated by a painting depicting the Last Supper. The artist, Mario Ferlito, was among 100 Italian veterans who attended the church's 50th anniversary service last summer. Mr Thomson had just found a set of pencil sketches for the Last Supper figures in the chapel roof. He says that when Mr Ferlito was shown the weathered drawings the tears rolled down his cheeks.
Scottish-born Mr Thomson was a sapper in the Royal Engineers in the war and served in Italy, lifting enemy mines. The irony of restoring an 'enemy' church has not escaped him but he is a man of compassion. He was demobbed in Wales in 1945 and decided to marry and settle there. In 1960 he bought the 20-acre POW site at Henllan and converted it into a small industrial estate and caravan site.
'The POW huts were just plasterboard on frames and some we knocked down and some were blown down with the storms,' he says. 'But the little one with the chapel just carried on. Don't put this down but many times I'd have been glad when it blew away because it was an eyesore on the caravan site. It stood up to all the storms and you got to the stage where you felt it was meant to stay.
'When me and my son Andrew decided to restore it, we took all the paintings down and put them on the floor with weights on them for 18 months to flatten them out. And of course they'd actually damaged the building when they built the chapel because they cut through the main beams to fit the arches and so the roof started dropping.
'Lifting the roof back was a major operation. Putting support pillars in was a big responsibility because we didn't want to alter the original and destroy anything. We were going to use steel beams to start with but they looked horrible so we took them out and used wood.
'The Italians started coming back here about 1975 when one of the POWs turned up with his wife. It was very touching for her to see the little chapel where her husband had been. He said he was going to a reunion in Italy and it was about 12 months after that I had a letter from Mr Ferlito, the painter.
'Last year I had a choir from Bologna, 30 of them, and they started singing in the chapel. It was really lovely and they let me tape-record it with a message in Italian for the prisoners coming back here.'
Italian communities at home and abroad are now trying to raise money to protect the little chapel from future storms. Rocco Bernacchio, a former POW at Henllan who settled in Britain, has written to his MEP in Nottingham, Ken Coates, asking him to help to raise a European grant. Professor Coates has written to the Prince of Wales asking for his support. According to the Labour MEP's office, the Prince has agreed to do what he can to help.
Mr Thomson, who has a horror of conservation officials poking around the site annoying his campers (viewing of the chapel is by appointment only) would welcome some help after years of personal dedication. Like Mr Ferlito, he wants the little chapel to remind future generations that there is more to life than shooting each other.
'What I really want to do is put a building over the present one that leaves the chapel inside as it is,' he says. 'Everyone's said 'You've done a wonderful job', but I'm old now and I can't do any more. I feel I've done my whack because it's been a labour of love, without doubt.'
Mr Ferlito is equally passionate about the little chapel. 'It was here that we tried to rediscover the meaning of our existence after that awful war,' he says. 'It is a very modest building, which has stood up in spite of neglect and bad weather. I think that in its humility it offers a small testimony to the Italian spirit which enjoyed the respect, affection and Christian hospitality of the Welsh people. Am I wrong to think that it also represents a fragment of Welsh history?'