If it exists, so if it is a myth are the activities taking place there, some say hide the aliens, I think it's a normal military base, if you wonder why everything is so guarded and that's because Americans are very obsessed with the terrorists from the 11-S, and therefore put security at military bases, public places ... Anyway, look at wikipedia for more information
http://es.wikipedia.org/wiki/% C3% 81rea_51