I have always had a very strong internal sense of direction and I've found that it relies strongly on knowing which way is north. This means that when I'm in a mall or other large building (malls are the worst) I get very lost and have to think hard about which way is which. I usually have to paint a birds eye view and know which stores are on which corner of the mall and orient myself that way. This also means that occasionally when I'm in a new city, I get north/south mixed up and am hopelessly lost