My family has a summer house out in the Stockholm Archipelago, it's on one of the tens of thousands of islands, it takes an hour to get there from home, and on our island there are about 60 houses, and there's ok infrastructure including public transportation to get there.

If you want more solitude, you just take the boat and go out to the more remote ones, there's nothing special or magical or mystical about "owning an island" to me, since that's how I spent my childhood summers.

Then I realized that archipelagos are pretty rare, which keeps the concept out of reach for most people.

Not to mention Switzerland, Norway, and Finland as well.