Sounds to me like where Lost takes place. Fascinating story from Annalee Newitz on io9.com:
You can’t find New Island on most maps of the Indian Ocean because its location was a secret for most of the twentieth century. But now one man has chronicled the long, strange history of its ancient inhabitants.
The ruins you see here come from a group known locally as the “Old People,” who probably started living on the island 43,500 years ago. In the modern age, the island was discovered in the late eighteenth century by two convict ships that crashed there on the way to Australia. One of those ships was filled with hundreds of female convicts, who eventually founded their own civilization on the island, based on sexual equality and paganism. Today the island is a bustling place, full of trains and welcoming visitors.
Unfortunately, you can only visit via a website created from the imagination of Lee (Rusty) Mothes, a worldbuilder who loves to draw maps and island landscapes. New Island is a place he’s been imagining for over a decade, and he finally put all his pictures and ideas about it into one place, which reads like a work of fantasy travelogue.
Read More of Annalee Newitz’s article “The Lost Culture Of New Island Is 43,500 Years Old” on io9.com

