The climb that left me frozen with fear
There are thousands of industrial chimneys in the Czech Republic, with many dating back to the late 19th Century - most are no longer used and a group of enthusiasts spend their weekends climbing the structures. Alastair Lawson joined them in Zelezny Brod, but soon regretted it.
I am 40m (130ft) up a 120-year-old chimney in the north-east of the Czech Republic and I am having a minor panic attack. My legs feel like lead weights as I look down on the tiny figures on the ground below me.
"Are you coming up or going down?" asks my guide, Martin Vystejn, as I cling for dear life on to the ladder.
The fear gripping me is so overpowering that my inclination is to do neither and remain suspended in mid-air about two-thirds of the way up the 52m (170ft) disused industrial chimney.
The other climbers seem unruffled by my agony and continue nonchalantly to make their ascent, neatly bypassing me on the ladder as I scuttle downwards.
So how did I end up in this predicament?
A few weeks ago, I read a Czech media report about the activities of the Union of Czech Chimney Climbers, a club set up mostly to climb, but also to survey and lobby for the preservation of the country's 5,000 to 6,000 industrial chimneys.
They invited me to join them as they scaled two disused textile factory chimneys located alongside each other in Zelezny Brod, north-east of Prague.
Every weekend and bank holiday the climbers meet at the base of a different chimney. They are men and women from all walks of life, including graphic designers, shopkeepers, accountants and students. The one thing they have in common is a passion - verging on an obsession - for being high up above the ground.
The age range is equally diverse - from teenagers to a 76-year-old former track-and-field athlete who whizzed up the ladder at high speed, making me feel even more inadequate.
Typical of the 1,000-or-so members' unbridled enthusiasm is Agnes, who estimates that she has climbed more chimneys than any other woman in the Czech Republic.
"I calculate that I have scaled 80,000m over the last decade," she tells me proudly. "I just love heights. I love the buzz they give me and I love the views from the top.
"I also really enjoy the company of fellow climbers - there's a real sense of comradeship here that you don't get in the city."
Martin Vystejn, the union secretary, is equally dedicated, leaving home most weekends with soccer-fan enthusiasm. He's now approaching his 20,000th climb.
"There is something enormously liberating about defying gravity, making it to the top and then witnessing the most amazing views. It's addictive," he says.
"My love of climbing chimneys has enabled me to travel all over our country and Eastern Europe and see new places. At the same time I have come to recognise how extraordinarily well-made these structures are."
But do his wife and family share his enthusiasm, I enquire.
"My wife has climbed five chimneys and for her that's enough," he says. "My son has completed almost 100 climbs and my daughter has done more than 20. So they understand it, I think."
The club does not confine its activities to the Czech Republic. Its members have climbed 1,500 chimneys elsewhere in Central and Eastern Europe, most recently the 360m (1,180ft) Trbovlje Chimney in Slovenia.
They hope soon to scale the GRES-2 Power Station chimney at Ekibastuz, Kazakhstan, which at 419m (1,377ft) is reputed to be the tallest in the world.
But there is no shortage of chimneys to climb in the Czech Republic. The union estimates that two-thirds of the country's chimneys are privately owned and more than 100 years old.
An important part of the club's work, says Vystejn, is to ensure that these "architectural gems" are not demolished.
Because the Czech Union of Chimney Climbers is the only government-recognised organisation of its kind, it is in a unique position to get permission to conduct climbs, form a database and lobby for the restoration of chimneys that have fallen into disrepair.
All this is a far cry from the club's origins. It began in the Soviet era when Vystejn and other teenagers gazed at the numerous 100m-tall chimneys around Prague and dreamed how liberating it would feel to climb them.
In the early 1980s, they decided to make the dream into a reality. What initially was a solitary adventure to defy the Communist authorities developed into a regular pastime.
"I don't think it's as dangerous as people think," reflects Vystejn, now a 53-year-old international transport manager.
"All climbers wear a helmet and harness and we have only had one fatality over the last 30 years.
"We believe that you are more likely to get killed crossing the road or riding a bicycle in Prague than actually falling off the ladder.
"But it can sometimes be difficult to believe that when you're suspended in mid-air 40m from the ground."
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