Looped square

The looped square (⌘) is a symbol consisting of a square with outward pointing loops at its corners. It is referred to by this name, for example, in works regarding the Mississippian culture. It is also known as the place of interest sign when used on information signs, a practice which started in Nordic countries in the late 1960s. Also, the symbol is known as Saint John's Arms or Saint Hannes cross (related to Swedish sankthanskors, Danish johanneskors, and Finnish hannunvaakuna), as Gorgon loop, and as command key symbol due to its use on the command key on Apple computer keyboards.

It is an ancient symbol used by several cultures, but remains in common use today. It belongs to a class of symbols which are called valknute in Norway.

The symbol appears on a number of old objects in Northern Europe. It features prominently on a picture stone from Hablingbo, Gotland, Sweden, that was created between 400 and 600 AD.

It is also similar to a traditional heraldic emblem called a Bowen knot.

In Finland, the symbol was painted or carved on houses and barns, and domestic utensils such as tableware, to protect them and their owners from evil spirits and bad luck. The oldest surviving example is a pair of 1000-year-old (Finnish pre-Christian period) wooden skis decorated with the symbol.

The looped square also appears on artifacts of the Mississippian culture of the southeastern United States.

In modern times, the symbol is commonly found in Ukraine, Belarus, Denmark, Estonia, Finland, Germany, Iceland, Latvia, Lithuania, Norway, and Sweden as an indicator of locations of cultural interest, beginning in the Scandinavian countries in the late 1960s. There has been modern speculation that it was chosen for its resemblance to an aerial view of Borgholm Castle; however, the symbol is well-represented in Scandinavian artifacts that predate the current castle by centuries.

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