They have become synonymous with the worst of the Great Terror of Stalin's reign, desolate places where millions perished, a shameful past the Russian state has since tried to ignore. But now the gulags of Siberia are back in business - this time as tourist attractions.
Some of the most remote and brutal labour camps will be opened up as Siberia, the new Klondike of Russia's rampant capitalism, tries to reinvent itself as a holiday destination.
The targeted area is a cluster of camps in the northern part of Krasnoyarsk in north-east Siberia, which has been almost perfectly preserved in the cold of the tundra. Also on show will be the remotest parts of the Trans-Siberian railway, built, it is said, "on the bones of the forgotten".
A 44-berth boat with the looks of a decaying gin palace, the Anton Chekhov, is being refurbished for the 950-mile trips up the muddy waters of the Yenesi river to the camps.
Because of the extreme weather conditions this will be possible only in June and July. However, for those wishing to indulge in this new chapter of "dark tourism" the costs are not exorbitant. A local travel company, Dula Tours, is offering a 12-day package from around £400 per head.
The same journey was made by inmates. They were on their way to Norilsk - north of the Arctic Circle, where they dug nickel - or Kraslag, a forestry camp which produced furniture. These were among a dozen camps, including some with women and children, in northern Krasnoyarsk, identified by number rather than by name.
Although most of them were emptied following Stalin's death in 1953, some prisoners were not freed until the late 1960s. Many were stuck in the system because their paperwork had disappeared. Others had nowhere to go to, having lost contact with their families, and drifted along, their health broken through years of hardship and neglect, dying before ever reaching home.
There is no shortage of literature about life in the gulags - an acronym from Glavnoe Upravlenie Lagerei or Main Camp Administration - by survivors including, of course, Alexander Solzhenitsyn. But despite the fact the camps had been technically available for visits for the past decade, there has been a remarkable lack of interest in doing so.
One reason is the sheer logistical difficulties in reaching the places. Also, obtaining permission to visit has involved a morass of bureaucratic paperwork.
All that, says Vladimir Demidov, managing director of Dula Tours, will change. "We will be able to organise these visits properly. There will be no problems, the local government is totally behind us," he said. "Nothing has been done to preserve these sites. But it's so cold that nature has preserved them perfectly.
"Most visitors have been Russians. We want to make this an international destination. People in the West know about the gulags and on the way up the river they can enjoy the wildlife and landscape of Siberia."
At Perm, on the western edge of the Urals, and the model for the fictionalised Siberian city where Dr Zhivago ended up in Boris Pasternak's novel, a museum has been built by local historians on the site of a former camp. The Russian government turned down requests for financial help, so a logging business using rusting machinery formerly used by inmates was set up to pay for the project.Reuse content