|Notable locations||Mount Justice, Happy Harbor, Rhode Island|
|Notable characters||Young Justice, Justice League Doom Patrol|
|First appearance||Brave and the Bold #28 (March, 1960)|
The Secret Sanctuary was the name given to a large cave deep inside of a mountain base in Happy Harbor, Rhode Island. Shortly after the Appellaxian invasion, the newly formed Justice League decided to use the cave as their secret headquarters. Aquaman discovered the original cave while exploring underwater grottoes. He informed the team about it when they needed a place to store the Appellaxian aliens. Shortly thereafter, one of the Appellaxians was abducted by the criminal organization called Locus. Financier Simon Carr provided the various facilities for the Secret Sanctuary, working at the anonymous behest of millionaire Oliver Queen aka Green Arrow. Simon engaged the services of his nephew Snapper Carr as the mechanic and general handyman for the Secret Sanctuary. Snapper knows the systems of the Sanctuary better than anyone, and he spends much of his time repairing, maintaining, and upgrading them. The Sanctuary is carved out of the solid rock of a mountain. The outer walls are thick stone over a layer of solid steel. Seismic sensors pick up any blows against the surface of the mountain and radar systems detect any approaching vehicles or individuals.
The Justice League stopped using the Secret Sanctuary after the Joker tricked young Snapper Carr into revealing its whereabouts, Justice League of America #77 although Aquaman's reformed version of the League temporarily reoccupied the Sanctuary for a while, Justice League of America #250 and the Justice League later set up shop in the Sanctuary until the organization was officially recognized by the United Nations. Justice League #1
They maintained their hidden base for many years until the financial backing of Bruce Wayne aka Batman enabled the team to established the Justice League Satellite in geosynchronous orbit above the Earth.
The cave remained empty for many years until some time ago when an abandoned alien entity found its way inside and began using it as a nest. Members of both the original Justice League as well as the nascent Detroit League worked together to remove this cumbersome entity from their former headquarters.
When the Watchtower was destroyed by Superboy-Prime in the run-up to the Infinite Crisis, the Justice League decamped to the Secret Sanctuary. From here they fought the Key.
When their brownstone headquarters were destroyed in a battle with an army of mercenary super criminals, the Justice Society borrowed the Sanctuary. However, they were asked to move out swiftly.
The Golden Age Superman likewise made use of a special hideaway known as the Secret Sanctuary, however this was an entirely different construct with no relationship to the Justice League headquarters. Located just outside Metropolis, Superman's Sanctuary functioned as a precursor to the Fortress of Solitude.
In other media
- The Secret Sanctuary based in Mount Justice appears at the end of the two-part Young Justice pilot "Independence Day". The Secret Sanctuary is given to the members of Young Justice as their base of operations and it is stated as being the Justice League's original headquarters prior to moving into the Hall of Justice. Happy Harbor is indicated as being in Rhode Island in Young Justice episode "Infiltrator".