If you start at the top of the cycle, C, and go in a counter clockwise direction, each new key and each new flat is a fourth higher than the previous key or flat. The key of Gbcontains six flats. After Gb, the next logical key would be Cb(containing seven flats). However, this is not practical, and rather than using the key of Cb, you would use the enharmonic name for this key, B (which contains five sharps).