By Robert Greenall
BBC News, Kurchatov
There can be few places on the planet as strange as Kurchatov, once the secret base from which Soviet scientists oversaw the testing of the USSR's nuclear weaponry.
Remains of animals used in the tests are preserved in a museum
It is impressively remote, a three-hour drive along an icy, potholed road across the frozen wastes of northern Kazakhstan - flanked on one side by the majestic Irtysh river and on the other by the test area.
The town was once a forbidden military zone, not featuring on maps and frequently changing its name. Known among other things as Nadezhda (Hope) and Konechnaya (The End), it got its current name - from the author of the tests - only after they ended in 1989.
And it evokes a mix of hope and despair - a once affluent town, largely abandoned by its Russian inhabitants after independence but seemingly now on the way back up.
The town was founded in 1947, just two years before the first tests. Stalin's notorious henchman, secret police chief Lavrenty Beria, even built his own dacha here to observe the effects of the new weapon.
This inoffensive-looking building has now been turned into a church, but the consequences of what happened nearby are not so easily forgotten.
In the years 1949-89 the Soviet Union exploded around 700 bombs on the test range.
In the first 14 years more than 100 tests were carried out above ground, including at least 30 at treetop height. For the last 29 years, they were underground.
It is the early tests which are thought to have caused the most damage, leaving huge areas contaminated and blighting the lives of thousands of local people.
THE FIRST TEST SITE
Surrounded by barbed wire and watchtowers with two soldiers for each
Concrete 10m high towers at regular intervals, connected by cables to
accumulators to measure the force of the blast
Military hardware including tanks, planes, fortifications and fragments of
rail and road bridges placed at the site
Animals tied to the military hardware
The human cost has been enormous, with premature death and birth defects at much higher rates than average. Cancer and suicide rates are still abnormally high in villages beside the polygon.
A museum in Kurchatov devoted to the nuclear tests brings home the horror. It shows a model of the site of the first test, where animals tethered to military hardware were put in the way of the blasts.
The gruesome results are also on show - pickled piglets, rabbits, horses and dogs with severe haemorrhaging and burns.
Kazakh President Nursultan Nazarbayev signed a decree closing the test range in 1991, but scientists are still struggling to deal with the contamination in what they describe as the equivalent of a huge minefield.
Though most of the land is now reckoned to be relatively safe, there are still lethal "hot spots".
The area is officially closed, but in practice there is little to stop people wandering inside. Many make a living by grazing animals on the land.
"People don't put any special clothing on, they just go there," town official Viktor Bardey told the BBC News website. "People go everywhere now."
Kazakhstan's National Nuclear Centre (NNC), based in Kurchatov, is trying to clean up the site and wants to map it out, but this is a lengthy process.
"We are involved in efforts to decide which bits of the test range should be made completely off limits, which should carry warnings and which can be used safely," says the centre's deputy director, Zhenis Zhotabayev.
Mr Zhotabayev comes from a village evacuated to make way for the test range when he was just three years old. He heard explosions from the first tests while living in the nearby town of Charsk.
But a lifetime in nuclear science has made him a keen advocate of his field and his attitude to the tests is difficult to gauge.
"At the time, no-one asked our opinion about what was happening," he says.
A visit to the NNC's headquarters in the town shows just who is really in charge around here.
Its sleek, modern offices and the official manner of its staff in receiving guests is in stark contrast to the rather ordinary town hall next door.
It is seen here as the great hope for the future in a town which lost more than two-thirds of its population after Kazakhstan's independence.
From a city of over 30,000 in 1991, it was reduced to just 8,000 as many Russian specialists returned home. Another military town nearby, Shaghan, was left completely deserted.
Empty buildings are everywhere, even at the town's core where a statue of founder Igor Kurchatov towers over a pleasant-looking square.
Much of Kurchatov has been empty since the Russians left
But Mr Bardey says the population is steadily rising again, and last year 700 people came to live here.
Construction money is coming in from various sources, and the town plans to restore six housing blocs over the next two years, he says.
Officials point to the town's young population. The majority of inhabitants are under 40, and there are over 1,000 schoolchildren.
"Everyone wants to invest in us now," Mr Bardey says. But it could take a sustained period of prosperity and financial support for Kurchatov to avoid the fate of its ghostly neighbour.