Tristan da Cunha,
United Kingdom

Personal experience

I visited this island group in early 2018, on an expedition ship between South America and South Africa.

This island group is often claimed to be the most remote inhabited archipelago on the planet.

It is one of the best places in the world to see several species, including Northern Rockhopper Penguin. It is estimated 85% or more of these penguins breed in the Tristan island group (the others are found in remote southern Indian Ocean Islands). Because numbers have severely dropped in recent years , this is considered an endangered species. The individual below was sitting on a rock at the jetty.

Northern Rockhopper Penguin (image by Damon Ramsey, www.ecosystem-guides.com)

There are also Atlantic Yellow-nosed Albatross. They are best seen from the cliff views a few minutes walk out of the main town. Although they can be seen at sea all around the southern oceans, the only place in the world they breed is here on these south Atlantic islands. 

Atlantic Yellow-nosed Albatross/Mollymawk (image by Damon Ramsey www.ecosystem-guides.com)

These cliffs are also a good place to watch the beautiful Sooty Albatross...

This island group also includes Nightingale, Gough and Inaccessible Islands.

Nightingale Island

I did not get to land on this island, but I was lucky enough to explore the coast (and watch some wildlife) from a zodiac.

Northern Rockhopper Penguin
Subantarctic Fur Seal

access

Due to the remoteness of these islands, they are obviously difficult to get to. I visited them with Silver Sea, a company that will goes there at the end of the Antarctic season, departing from Ushuaia in Argentina and arriving at Cape Town in South Africa.