That record has so far held, but, given that Ap Lei Chau includes some undeveloped hills, an island more heavily covered with highrises could surpass this island’s population density.

(Image courtesey Dave Berezansky)

It has formed new land, but its status is unclear:

• Some sources report a new island. That would mean that it was the world’s newest volcanic island.
• Pictures and this account suggest that it may have started as two vents, one in the sea and the other on Hunga Ha’apai, and that any new land created was soon joined to this pre-existing island. This account says Hunga Ha’apai has grown by thousands of square feet.

National Geographic has video, as does Scientific American.

It is in Canada, but I have confirmed my suspicions that the strongest candidate is not on Newfoundland but on Victoria Island, in Nunavut.

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This island in a lake on an island in a lake in south-central Victoria Island, at 69.7928° north, 108.2411° west, is 4 acres / 1.6 hectares, easily beating its rivals in size.

These include Canada’s:

• largest island
• largest lake island
• largest island on an island
• most populous island
• tallest island
• tallest lake island
• most common island name

1. Long I., NY –1401
2. Marsh I., LA — 117
3. Mount Desert I., ME — 106
4. Martha’s Vineyard. MA — 97
5. Merritt I., FL — 93 (boundaries debatable)
6. Saint James I., FL — 79 (partially riverine)
7. Johns I., SC — 75
8. Matagorda I., TX – c. 71
9. Port Royal I., SC — 70
10. Saint Helena I., SC — 59
11. Staten I., NY — 58.7
12. Point Au Fer I., LA — 58
13. Edisto I., SC — 54

These include the:

• largest American island
• tallest American island
• highest American island
• largest American lake island
• most heavily populated American island
• most common name for American islands

Elbruz.org has long had a nice piece on recursive islands and lakes, but they get the final one wrong, saying that the island in Taal’s Volcano Island’s crater lake is the largest island in a lake on an island in a lake on an island.

That Filipino “triple island” is only about 1 acre / 0.4 hectare.

The largest known island of this sort (subject to further exploration; some Arctic areas are poorly mapped) is the largest island in the largest lake on Glover Island, in Grand Lake on Newfoundland.

Glover Island, the world’s second-largest island on an island, has a many lakes on it, and the largest has about 17 islands. The largest of these is 2 acres / 0.8 ha. When I visited it, it supported its own little patch of woods.

They visit Namucuo (commonly known as Nam Co or Nam Tsho, a high salt lake.

Teng writes:

It was evident that all mountain ranges converged on the lake, and there was an island emerging from the centre of the lake. Together, they formed “The Dragon Celebrating Pearl Formation” that facilitated Tibet’s spirituality.

Incidentally, Teng (and other sources) refer to Nam Co as “highest lake on earth,” but there are other, higher lakes, including Orba Co, the site of the highest islands in the world.

Hashima is small (6 hectare / 15 acres), and was owned by a coal mining company, which housed the miners on the island. Writes Google Sightseeing:

When space for the workers began to run out, they built Japan’s first large scale reinforced concrete apartment block on the island in 1916. More concrete tower blocks followed, and by 1959 the population of Hashima reached its peak of 5,259 — an astonishing 1,391 people per 10,000 square metres within the residential district — which is said to be the highest population density ever recorded in the world.

That would indeed be the most densely populated island known: 227,000 people per square mile, or 88,000 per sq km, surpassing the current record holder, Ap Lei Chau, which houses 160,000 per sq mi / 60,000 per sq km. This is all the more impressive given that Hashima was not connected to mainland Japan by bridge.

The island is now evidently deserted.

The island, at Home Reef, appears substantial: as of August, when it was discovered by a Swedish yacht whose crew took these pictures, it had at least three small hills.

The odds are that the island will not last long. The Home Reef volcano produces islands regularly, and did so in 2004, 1984, and twice in the 1850s, according to NASA and the Smithsonian’s Volcanoes of the World.

Image courtesy of NASA.