The flag of Switzerland consists of an equilateral white cross (length to width ratio of 7:6) centred on a square red field. The white cross itself is referred to as the "Swiss Cross". The ratio of the Swiss flag is 1:1 - interestingly, the Swiss flag remains one of only two square shaped sovereign state flags (the other square flag is that of the Vatican City). However, the actual design of the flag (plain with a cross) is extremely typical of many European state flags from the medieval era.
The white cross was used as a field sign of the Old Swiss Confederacy dating back to the 13th or 14th century. The present day design became the official flag of Switzerland on 12 December 1889, at which time the symbolism of the white cross was noted by the Swiss Federal Council as being "at the same time the Christian cross symbol and the field sign of the Old Confederacy".
The flag of Switzerland flying