Anchorage, Alaska, and I’m about to embark on arguably the world’s greatest sea voyage. There’s an obvious buzz of excitement among the 1,070 cruise passengers but also – and I don’t think I’m imagining this – a faint air of trepidation.

Trepidation, because Crystal Serenity is about to become the largest ship ever to attempt the Northwest Passage. At 9pm this evening the ship will set sail from Seward, Alaska, on a 32-day, near 1,000-mile journey via Canada and Greenland to New York.

This 900-mile “short cut” between the Pacific and Atlantic oceans across the icy roof of North America has defied and claimed the lives of countless seafarers since John Cabot first sought the passage in 1497.

"Crystal Serenity is equipped with state-of-the art forward-looking sonar and ice-detecting high-resolution radar" Credit: rex features

There have been around 240 transits in the 110 years since Roald Amundsen made the first successful crossing in 1906. Amundsen’s trip took three years. Serenity's voyage is scheduled to take eight days, part of a 32-day cruise that will see it arrive in New York on September 16.

Most of those 240 transits, including 17 last year, have occurred since 2007, the first time in recorded history the Passage was considered “ice free” in summer, a result of ocean warming.

Crystal CEO Edie Rodriguez told the BBC's Today programme last month that the line had gone “beyond the call of duty” to meet requirements needed to take the ship into a pristine environment.

“From the low-sulphur marine gas oil that we are using to engaging the local community and involving them in our plan to ensure we don't disturb their environment, we have taken many, many precautions to ensure we don't disturb their environment,” she said.

"We are in the company of 21 guest scientists, adventurers and lecturers, from marine biologists and divers to climatologists and naturalists"

Serenity is not the first passenger or cruise vessel to make the trip – the Lindblad Explorer was the first to carry paying passengers in 1984, and in 2012 The World, a cruise-size vessel, made it through with 481 passengers. She is, though, by far the largest – 13 decks high, 820ft long, and weighing in at 68,870 tons.

And size is a problem in the NW Passage, not a defined route but a labyrinth of possible waterways, just 10 per cent of which has been charted. Unknown rocks, shallows and currents will present constant challenges. So will sea ice.

This 900-mile “short cut” between the Pacific and Atlantic oceans has defied and claimed the lives of countless seafarers

Things have gone wrong in the past. In 2010 it took a Canadian icebreaker 40 hours to evacuate just 120 passengers from the 330ft Clipper Adventurer when it ran aground on an underwater cliff.

At times, Serenity will be 1,000 miles and at least 11 hours’ response time from coast guard assistance.

But she will not be alone. The RRS Ernest Shackleton, an ICE 05-Class icebreaker, chartered from the British Antarctic Survey, will provide logistical and ice-breaking assistance and emergency supplies, and there are two helicopters to help scan for ice.

The Shackleton’s presence is part of the meticulous preparation Crystal Cruises has undertaken for this pioneering cruise, which sold out in just three weeks, despite prices of between $21,850 (£16,900) and $120,995 (£93,660) per person and excursions that cost up to $6,179 (£4,780).

We are in the company of 21 guest scientists, adventurers and lecturers, from marine biologists and divers to climatologists and naturalists – some of whom I hope to meet.

“We have been planning this historic sailing for two years,” said Crystal CEO Edie Rodriguez,” who was on board today to greet passengers, “working closely with expedition experts, as well as Transport Canada, the US and Canadian Coast Guards and local agencies along the route to ensure the ultimate safety for our guests.”

Crystal Serenity is also equipped with state-of-the art forward-looking sonar, ice-detecting high-resolution radar, thermal imaging equipment and specially designed searchlights to help identify hazards at night.

It sounds reassuring, and having already explored the ship, which is looking magnificent, settled into my balcony stateroom and eaten my first on-board lunch, I have no fears over my creature comforts.

But a vast ship, narrow channels, uncharted seas, summer icebergs, the 36,000 islands of the Arctic archipelago and a passage through the waters that claimed the Titanic? I’ll get back to you.

crystalcruises.co.uk