If you want to build a vacation resort where the ocean water is cold and inhospitable, you'd better come up with something incredible to attract people. That's exactly what Chilean developer Fernando Fischmann did with his kilometer-long artificial lagoon. Equivalent to 6,000 eight-meter long swimming pools, the lagoon is the world's largest swimming pool in the world. This project was not for the faint-hearted; it took 10 years to develop the new technology for capturing, filtering, and recirculating ocean water. But guests are sure to appreciate it. The surrounding ocean water is around 62 degrees while the lagoon maintains a more swimmer-friendly 78 degrees. I especially love the photos of guests sailing in the lagoon alongside swimmers and kayakers as shown on the resort website. Now that the project is completed, Fischmann is ready to go worldwide. He recently launched Crystal Lagoon Corporation, using the technology he developed to sell more arena-sized swimming pools.