A megayacht is typically a vessel over 200 feet in length, while the fairly new term gigayacht describes yachts more than 300 feet in length. Gigayachts are some of the largest and most expensive ...

Roman Abramovich's gigayacht Eclipse. The largest private yacht in the world at 163 meters, "Eclipse" is believed to feature around 24 guest cabins, two swimming pools, and a mini-submarine.