Where is the GAC folder??

Hi I am bit confused about the location of the Global Assembly Cache. I have read at many palces that it is located at c:\windir\assembly but when I try to check this with windows explorer I did not find anything like "GAC" in it. When I check the same on command prompt then I was surprised to see the "GAC" folder was ther under the "assembly" folder. Can anyone explain me this? Thanks and Regards, Virendra ...