Poland's Wieliczka salt mine is a Unesco heritage site. But mind the steps, says Michael Church
There were 13 of us waiting at the mouth of Wieliczka salt mine on the fringe of the industrial wasteland south of Krakw. For most of us it had been a toss-up between this and a day-trip to Auschwitz, and as we huddled in the cavernous entrance hall, we wondered if there would be be much difference. A voice boomed out: "Good afternoon. My name is Margaret. I am your guide. We go now." I'd heard this voice before in Poland: it's the voice you encounter in museums, telling you to pay attention, berating you for lagging behind, furiously rounding on you when you have the temerity to cast aside your regulation museum overshoes. It's a voice that harks back to the glory days of Communism.

"First we go down these stairs." Er, our guidebook mentioned a lift, and my wife had torn a cartilage in her knee. "No, we walk. It is a nice walk."

My wife became mutinous. She announced that she'd sit this one out. "But you must come. What will you do otherwise?" My wife replied that she would be happy reading her book, and playing with the pit-head cat. Margaret looked thunderous, and herded the rest of us down into the gloom.

Suddenly I was aware of a big difference between Margaret and the rest of us. She was wearing a hard hat, we were not - it was like the pilot of an airliner having a life-jacket, but denying the luxury to his passengers. Maybe it was just Margaret's badge of office.

Our group included an elderly couple from Surbiton and a family of fat Americans, who didn't sound happy. We walked on, and on, and 378 steps later we reach Level One. "Now I must tell you. No smoking. No touching the electrical installations. No touching the sculptures. The air smells good, no? It is the diodium in the atmosphere." Not a word I knew, but never mind. "Very good for asthmatics. Take deep breaths. Sick people come here to be cured." And claustrophobics, presumably, to be driven mad, and people with knee injuries to be made so much worse that they need hospital treatment ...

But we began to see why this mine has been designated a Unesco heritage site. We arrived at the Nicolas Copernicus chamber, commemorating the Polish astronomer's visit here in 1493. His salt statue reared over our heads. The adjoining chamber, St Anthony's Chapel, is a gem: a graceful arch with spiral pillars, a solid salt sculpture that has stood here since the 17th century. "This is where the miners came to pray before starting work. The draughts of air have been cut off to prevent the sculpture melting, particularly in summer. Down here it is damp in summer, dry in winter."

We walked on through narrow passages, their walls and roofs shored with logs. We passed a salt King Casimir the Great, salt tableaux vivants from Polish history, and many salt dwarfs humping salt logs and playing salt leapfrog.

Then Margaret halted in mid-sentence and addressed an Italian couple who had attached themselves to our group. "Who are you? You are not of my group. I am not speaking to you." The couple apologised and said they'd got lost. "That makes no difference. You may not listen to me." They politely pointed out that they could hardly avoid doing so. Then she beamed. "You are the countrymen of my best friend, John Paul the Second! You may stay with us." From this point on, every sentence of her commentary was duplicated in Italian.

We weaved through more passageways, descended many more flights of stairs, then we reached a chamber as big as an aircraft hangar. This was the Chapel of the Blessed Kinga, 60 yards long, 40ft high, and hollowed out of one solid block of salt. It was breathtaking. "Around the walls you will see carved bas-reliefs. The Flight Into Egypt, the Marriage at Cana, the Massacre of the Innocents. We are 100 metres below ground. The acoustics are so good that they have concerts here. And six times a year they hold a religious service." All the artists responsible were miners: Polish manual workers were always a cut above the rest.

On again, to a high chamber with a Star of David gouged out of the salt face. This was where the occupying Germans set up an aircraft engine factory in 1944, using forced labour from a Jewish encampment they had placed nearby. All the Jewish labourers were finally taken off to their deaths, bar two boys who hid in a side shaft and were sheltered by miners.

At one point two real miners emerged from a tunnel: Wieliczka may be a tourist attraction, but it is still a working mine. We passed a dark green lake of brine, and entered a series of chambers. Here there were colossal treadmills and giant capstans that were once turned by teams of horses, and there was a rope to the surface from which clung 16 life- size wooden figures: this was how the miners got back to the surface.

Margaret's only concession to human frailty came when she packed us into a metal cage and sent us up through the blackness, to emerge blinking in the sun. My wife had made friends with the cat, and passed a pleasant hour. My hour had been, well, certainly interesting.

Krakw facts

Getting there: You can fly from Gatwick to Krakw on British Airways or the Polish airline LOT, or from Heathrow or Manchester via Warsaw; Polorbis (0171-636 2217) usually offers fares below those charged by the airlines themselves. Expect to pay around pounds 240 return for travel from London in July. Alternatively, take the bus - Eurolines (01582 404511) has a student return fare of around pounds 100 from Victoria coach station to the city.

Visas are no longer required for British passport holders visiting Poland.

More information: the Polish National Tourist Office, First Floor, Remo House, 310-312 Regent Street, London W1R 5AJ (0171-580 8811).