The Northwest Passage, the Arctic route linking the Atlantic and Pacific, gnawed away at Roald Amundsen until he finally navigated a route in 1905.
It had claimed the lives of countless brave, often foolhardy explorers, most notoriously the 130 men of the 1845 Franklin expedition, who along with their two ships, simply vanished into the icy wasteland.
But today, thanks to climate change and the associated rapid loss of sea ice, the Northwest Passage has become one of the most dramatic and visually magnificent tourist destinations.
This year in high summer, a small number of cruise ships will embark on the journey, confident that they will be able to navigate their way through the evaporating ice. It promises to be a spectacular trip: tourists are all but guaranteed to see polar bears, walruses, whales, seals, and migratory birds in a setting of extraordinary beauty; but it is a scenario that has provoked an ambivalent response within both tourism and scientific communities.
"It's a tough question because nothing beats seeing a place at first hand and the Arctic is a place that really resonates with people," said Kristina Johnson, a spokeswoman for the Sierra Club, the oldest conservation organisation in the US. "You cannot begrudge those who have the chance to make such a trip, but it's really sad that climate change makes it possible. But there is a responsible way to go with tourism in the Arctic, and an irresponsible way.
"There has to be a balance, because the more people who get to experience the raw Arctic for real, and the more they see polar bears in the wild, the more likely they will be moved to campaign for its protection."
The concern of conservationists is that a cruise ship may hit an iceberg, or spring a fuel leak, causing devastation to a pristine wilderness. In response, cruise operators to Svalbard, the northerly archipelago owned by Norway, and Greenland have established the Association of Arctic Expedition Cruise Operators, which is dedicated to managing environmentally friendly and safe expeditions in the Arctic. The organisation comprises 13 companies from seven countries operating 21 vessels, with sizes ranging from small sailing yachts to cruise ships with up to 320 passengers.
"The polar regions are becoming more popular not because the ice sheets are melting but because clients are looking to push boundaries," said Jarrod Kyte, UK manager of Peregrine Adventures, which plans to sail through the Northwest Passage this summer.
Mr Kyte acknowledges the contrary position of companies such as his - taking people to areas of great conservation value simply because the melting ice sheets now enable them to do so. "We can offer tours to places like the Northwest Passage without certain operational headaches," he said. "Five years ago, you would have needed an ice breaker; now you just need an ice-strengthened vessel.
"You can't protect what you don't know. We have nothing to gain from treating the Arctic and Antarctica like exhibits in a museum. We are not running fun cruises where people play bingo or pool aerobics. Climate change and conservation are big topics for our lecturers. It makes what is happening far more tangible for our guests."
Concerns about polar tourism extend to Antarctica, where visitor numbers have expanded in recent years. Bolstered by a safety record that was second to none, cruise operators raised the number of visitors from 4 698 tourists in the 1990/91 southern hemisphere summer to 24 281 in 2003/04. The release of the documentary March of the Penguins has since pushed numbers above 30 000. The largest vessel going to the Antarctic last season, the Golden Princess, carried more than 2 000 people.
But last year, the incident that conservationists feared finally happened: in November the MV Explorer hit an iceberg and its 154 passengers and crew had to be evacuated. No one was seriously injured and there was no fuel leak, but the accident has prompted a review of procedures for cruise ships to Antarctica.
Others feel more control is required. The Antarctic and Southern Ocean Coalition (ASOC), a large grouping of environmental organisations, is alarmed that visitors can parachute, ski, ride a motorbike or fly a helicopter over the continent. Jim Barnes, executive director of ASOC, believes that progress has been made in the past two years. "A signal has been sent to the tour operators that some types of tourism are undesirable, such as large ships carrying more than 500 passengers and land-based tourism infrastructure. But there are still no legally binding measures in place on any aspect of commercial Antarctic tourism."
Overall, ASOC fears that tourism will become entrenched as the main Antarctic activity in terms of scale and influence, with an erosion of intrinsic values of Antarctica and the primary role of science and environmental protection. "There may be some educational benefits from some kinds and scales of tourism so long as it is conducted properly - but 'properly' needs to be defined carefully," said Mr Barnes.