Airlines have opened up access to a myriad of adventurous, far-flung destinations, but there are still some places you can only really access by sea.

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Many are serviced only by small-scale passenger ships offering specialist itineraries. But even larger liners are getting in on the act, purchasing exclusive islands purely for their customers’ use.

So if you really want to get away from it all, why not try some of these?

South Georgia

Battered by wind and angry weather, this remote island in the South Atlantic Ocean may be inhospitable for humans, but it’s home to the largest king penguin colony in the world. There are no landing strips and its distance from mainland means it’s impossible for helicopters to make the return journey with one fuel tank.

Explorer Ernest Shackleton famously crossed the island to safety 100 years ago, after being lost at sea for two years, and visitors can replicate part of his trail which ends up at an abandoned whaling station.

But the big draw card here is wildlife; sparring elephant seals, swooping albatross and the South Georgia pipit, rescued from extinction, can all be seen.

Most travellers visit as part of a voyage to Antarctica, although One Ocean Expeditions offers a pioneering 15-day South Georgia In-Depth tour including a charter flight from Stanley (Falkland Islands).

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Papua New Guinea

Although flights service the mainland of Papua New Guinea, many coastal areas and small islands can only be reached by sea. Some communities are so remote their only contact with the outside world comes when cruise ships dock.

Each community has their own culture to show off, often in the form of sing-sings: smile at the playful choreography of the Trobriand islanders and paddle upstream in dug-out canoes through the rainforests of Tufi Fjords, where performers are adorned with feathers from the Birds of Paradise.

The diving here is also superb; dive or snorkel above pristine fringing reefs. Protected by the horseshoe-shaped remains of a volcanic caldera, Dicky’s Place on Garove Island is excellent for shallow dives.

Half Moon Cay, Bahamas

In the past few years, there’s been an accelerating trend for cruise ship companies to buy private islands and this is one of the more popular options on offer. Purchased by Holland America Line, the Bahamian hideaway 100 miles southeast of Nassau serves as a private retreat for passengers on HAL’s Caribbean and Panama sailings. 

Private cabanas with butler service can be rented along the two-mile crescent beach, and families are catered for with a water sports centre and aqua park. Activities include snorkelling with stingrays, parasailing and horseback riding by the sea.

Away from the action, it is pure wilderness; only 2% of the 1,700-acre island has been developed.

Wrangel Island, Russia

The High Arctic region is the realm of the polar bear. Most wildlife lovers seek them in Norwegian archipelago Svalbard, but tour operator Wildlife Worldwide has launched an exciting new itinerary to Russian outpost Wrangel Island, 140km off the coast of Siberia.

A special permit and ice-strengthened vessel are required to visit, meaning few people have the opportunity to tread on tundra where woolly mammoths once roamed.

Pick your way through ancient tusks which still litter the island, and keep an eye out for walruses, snow geese, Arctic fox and 400 female polar bears who raise their young here. 

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Sub-Antarctic Islands, New Zealand

If you thought New Zealand was far away, try its Sub-Antarctic islands, a collection of UNESCO World Heritage wildlife sanctuaries sandwiched between South Island and Antarctica. Yellow-eyed penguins waddle through the rata forests of Enderby Island, and albatross nest on the grassy slopes of Campbell Island.

Birders will be in absolute heaven (look out for the Campbell Island teal, one of the world’s rarest ducks) and anecdote-hungry travellers can boast having visited a place seen by woefully few people each year.