The Secret Sanctuary was the initial headquarters of the Justice League of America, within a mountain just outside Happy Harbor, USA, Earth-One. It was later abandoned when the Joker discovered its location, thanks to the betrayal of the team's mascot Snapper Carr in a moment of weakness. The headquarters was state of the art, with several rooms and chambers to satisfy the various needs and functions of the up-and-coming team, as was its doppleganger on a parallel world.
The Justice Society of America initially operated out of a rented hotel room in the New York City of Earth-Two, which they allowed the All-Star Squadron to borrow from time-to-time, before moving to their Civic City digs. Then, during their early years as a team the Justice Society members were twice held captive in the seaside sanctuary of the Brain Wave, a stone tower near Sharktooth Bay which correlated to Happy Harbor. Not only were the male members of the Society drawn to this locale but also their girlfriends and teammate Wonder Woman. Then it was demolished by its owner's own malevolent machinations, forever a testimony to the folly of felony!
Further correlations to these two bases can be found in the use of the Secret Sanctuary years after it was abandoned... by the Justice League's arch-foes the Injustice Gang! That their base would be used by their foes... while a future member of the Injustice Society, Brain Wave, would use Sharktooth Tower as his own base of operations.. shows that great parallels exist between these two planes of existence!