My new novella is going to be a shipwreck story mostly set on an island in the Indian Ocean. I was open to either using a real island or inventing my own, but if I invented one, I wanted it to have realistic topography and flora and fauna. So I started out on Wikipedia, where I found a list of islands in the Indian Ocean. I focused on islands close to Madagascar, but not too close, because I want my hero and heroine to be enough off the beaten seapath that they've given up hope of rescue by the time another ship happens by.
I'd almost decided to invent my own when I clicked on the link for Tromelin Island. It's a tiny little teardrop-shaped scrap of land, more sand than anything else...and yet it supported a group of shipwreck survivors for 15 years in the 18th century. If you click on the link you'll find a remarkable story. A French ship transporting slaves was wrecked there, and the surviving sailors built a boat to sail for Madagascar--but left the slaves behind because there wasn't room for them. Somehow a rescue attempt was never made, but more than a decade later a ship happened to pass by the same spot and saw signs of life.
I wish there were more details known about the survivors, and a writer with slightly different interests could make a hell of a novel about their experiences. Me, I'm just going to borrow their island, though I doubt I'll actually name it in the story. It's small enough to be claustrophobic, which I want, since my hero and heroine have a history. But they'd have plenty to eat, also a big plus. I may be gritty for a Regency writer, but I don't think I can make starvation sexy.