The military built a number of ghost towns during WWII.  Fort McGilvray near Seward housed 500 troops at Cains Head.  Today you can still see a few ruins, including fire hydrants sticking up out of the floor of the rain forest there.  A military base and marine transshipment facility was also built in Excursion inlet near Gustavus in SE Alaska housing thousands of military personnel, but the whole 60 million dollar facility was later dismantled by Italian and German POWs.