Standing 100 yards from the husk of Chernobyl’s Reactor Number 4, the click-click-click of the Geiger counter becomes alarmingly insistent. One step closer and it is beeping and flashing. Our guide gives a reassuring smile. “It’s fine,” she says. But she knows we know she would say that.

Soon, we are back on the bus and driving away from the Vladimir Ilyich Lenin Power Station, better known as Chernobyl. When I first visited, two years after the world’s worst nuclear accident, it took weeks of negotiating with the Soviet authorities to gain access to the plant. Today, busloads of visitors arrive on an almost daily basis. For less than £100, the adventurous can take a one-day tour of the so-called “dead zone”, the contaminated 10km circle drawn around Chernobyl after the accident in the early hours of 26 April 1986.

Aside from the frisson of standing yards from the shattered reactor, tours include a visit to an abandoned kindergarten, and the once top-secret Woodpecker “over-the-horizon” Soviet listening station. You can even traipse through the rural shack of a “self-settler”, one of the handful of elderly people living illegally in the dead zone, most of them without electricity or running water.

‘There is total silence. Not even the birds sing’: the trees that once lined the streets of Pripyat have now overtaken them. Photograph: Gleb Garanich/Reuters

The most bizarre, however, has to be a visit to Pripyat, the ghost city that was home to Chernobyl workers until it was hastily evacuated 36 hours after the accident. In 1988, the city’s public address system was still broadcasting music that drifted eerily through the abandoned streets. Today, those same streets have been reclaimed by the trees that once lined them and there is total silence. Not even the birds sing.

The zone is punctuated with radiation hotspots and only the reckless wander off the agreed track

Thirty years on, I recall the eek moment when scientists at the nearby research station – now also closed – presented me with a bunch of unnaturally large “Chernobyl roses”. “Get rid of them,” hissed the translator as we walked away. Perhaps I should have worried, too; the same scientists had shown us a bizarre collection of pine saplings grown from the seeds of what became known as the “Red Forest” around Chernobyl after radioactive dust made the trees glow – and they had weird deviations, double centres, needles growing backwards…

Holidaymakers rubber-necking the scenes of catastrophes used to be called “disaster tourists”. Today, those helping travellers to beat a path to Chernobyl, Fukushima or Auschwitz prefer to talk of adventure tourism. The Ukrainian authorities refer euphemistically to “education” rather than “tourism”, mindful of accusations they are profiting from tragedy.

Empty shell: visitors to Pripyat’s poignantly decaying public park. Photograph: Lynn Hilton/REX/Shutterstock

Although it seems adventurous, the itinerary must be agreed with Chernobyl officials in advance and rigidly stuck to. The zone is punctuated with radiation hotspots and only the reckless wander off the verified and agreed track.

Dylan Harris, owner of the British-based Lupine Travel, whose catalogue includes Chernobyl, North Korea, Iraq, Iran, Eritrea, Somaliland and Turkmenistan, says he can understand why some might view such trips as “morbid and voyeuristic”. But, he explains, “I genuinely don’t think it’s the reason why most people want to visit these places. I believe it gives a much deeper understanding of what happened there. Everyone has heard about the Holocaust, but nothing can prepare you for the feelings that engulf you on a visit to Auschwitz.

“The Chernobyl disaster was a big part of my growing up in the 80s,” he continues. “It was covered extensively in the news. Eastern Europe always felt like another world that could never be visited and therefore always intrigued me.”

Timing, says Harris, is important. “A couple of months after the Fukushima disaster, I was contacted by somebody in Japan who offered to set up tours for me around the area. I rejected the idea immediately. It was much too soon to gain any kind of benefit or rewarding educational experience from it. It didn’t sit right with me – it felt totally dark and voyeuristic. Hundreds of people had been killed, lives had been destroyed, homes washed away. It was still completely raw.”

Dried up: Pripyat’s swimming pool. Photograph: Lynn Hilton/REX/Shutterstock

Dominik Orfanus of Chernobylwel.com has been running tours to Chernobyl for eight years. Most tourists, he says, are European and male. He says his company gives part of its profits to organisations helping Chernobyl children, and recently bought a cultivator for a group of self-settlers whose old horse had died.

“Chernobyl is my passion. I love the place. When we take people around, they can understand what happened, they see how people’s lives changed from one day to the next. We have people tell us the visit changed their values because they realised how fragile life is. There is a big human and emotional side to visiting Chernobyl. It wouldn’t work if we didn’t give something back.”

Leaving the zone, there is a moment of high drama as we pass through radiation detectors that appear to be the same ones I saw back in 1988. No alarms sound. The guide says we have probably absorbed less radiation than on a transatlantic flight.

“So we won’t glow in the dark?” someone asks. Everyone laughs.

Essentials

Ukraine International Airlines flies (flyuia.com) from Gatwick to Kiev, from £112 return. BA (ba.com) flies direct to Kiev from Heathrow, from £56 each way.

Lupinetravel.co.uk and chernobylwel.com arrange tours to Chernobyl, Pripyat and other areas within the exclusion zone. Prices start from £100 for a day trip, Geiger counter included.

British passport holders don’t need a visa for tourist visits.