Skerry cruisers (or Square metre yachts) are yachts, usually wooden, which are constructed according to the Square metre rule. Originating from Sweden, they were historically most popular in the Baltic Sea, though some classes also saw popularity in other European countries and USA. Skerry cruisers are construction classes, meaning that though the boats are not identical with each other, they are all built according to same formula, making them broadly comparable in size and performance. Most skerry cruisers are slender boats, with low freeboards and tall rigs.