Knowing the two important principles generalized earlier in this chapter, you can work out the key signature of any key by knowing where it lies in what is termed the cycle of fifths. Why is it called the cycle of fifths? To answer this question, you need to look at an intriguing anomaly. After B major in the cycle, which has five sharps, comes F# major, which has six. Similarly, after Db major in the cycle, which has five flats, comes Gb major, which has six. Notice that the keys with six sharps/flats have the same keynotes—F# and Gb.