When you think about islands, your mind automatically leans toward warm and sunny, beaches and palm trees. Sure, there are a few notable exceptions. Manhattan, Manila, and most of Hong Kong certainly don’t fit that mold. But otherwise, you expect tropical, quiet, and undeveloped. Santa Cruz del Islote doesn’t play by the rules.

You’d be forgiven for expecting a tropical paradise on Santa Cruz del Islote. It is part of the Archipelago of San Bernardo, a group of coral islands southwest of Cartagena in the Gulf of Morrosquillo, after all. But while the nine other islands are known for their white sand, mangroves, and sea turtles, Santa Cruz del Islote is famous for being the most densely populated island on Earth.

That’s right. This tiny Caribbean island—covering only 2.4 acres—is the most crowded island in the entire world. The island was empty, of people at least, until the late-19th century, when fishermen from Isla Barú arrived. Finding no mosquitos—thanks to the way the winds blow—they decided to stay. Santa Cruz del Islote is now home to about 1,200 people, 90 colorful houses, a few shops, one school, and a single courtyard that’s the size of a volleyball court. There’s no doctor. Electricity only runs, by generator, a few hours each day. While ferries take residents to other islands or the mainland for work, to visit the cemetery, or to attend classes beyond primary school.

But having so many people in such a small space doesn’t mean the island isn’t peaceful. Since everyone lives so close together and knows each other so well, there is little to no crime on Santa Cruz del Islote. Curious visitors arrive to wander through the maze of alleyways, snorkel in the clear water, and talk to the local fishermen. They watch the Colombian Navy drop off fresh water, which arrives once every three weeks. Plus they discover a truly unique place in the world, something that’s becoming harder and harder to do. Forget the rules.