Most cruises promise relaxation. Swan Hellenic's promise is stranger and more interesting: breakfast near a polar bear, lunch with village elders on Papua New Guinea's Sepik River, and a few days later the rusting wrecks and shifting dunes of Namibia's Skeleton Coast.

The line runs small luxury expedition ships to the parts of the map that big vessels simply can't reach — the coral-fringed islands of Melanesia, the frozen silence of Svalbard in the high Arctic, the fog-bound Atlantic edge of southern Africa. Ships carry expert naturalists, historians and anthropologists, so the days at sea are as much part of the trip as the landings: you arrive at each community or iceberg field already knowing what you're looking at.

The real differentiator is access. Zodiacs take guests ashore in places with no port — little-visited villages in Papua New Guinea, sea ice where polar bears drift past, desert coastline where the Namib meets the ocean. The company frames its approach around respectful cultural engagement rather than drive-by tourism, which matters when your shore excursion is someone's home.

It's worth knowing what kind of traveller this suits. If you want waterslides and a buffet the size of an airport terminal, look elsewhere. If you'd rather be one of perhaps a couple of hundred guests, standing transfixed amid Arctic icebergs with a glaciologist on hand to explain them, this is the format. No two sailings are alike — routes depend on ice, weather and wildlife, and that unpredictability is the point rather than a flaw.

Highlights across the programme include whale-watching off West Africa, travelling the length of Namibia's Skeleton Coast, Arctic sailings around Svalbard, and cultural journeys up the Sepik River in Papua New Guinea, one of the least-visited countries on earth.

For holiday planners, the takeaway is that expedition cruising has matured. You no longer choose between comfort and remoteness — Swan Hellenic's proposition is that you can have a proper bed, good food and expert company while still landing on a beach no cruise ship has ever docked at.