hideout
A secret place where someone hides from being found.
A hideout is a secret place where someone goes to avoid being found. Bank robbers in old Western movies might have a hideout in a canyon where they stash their loot and lie low until things cool down. Kids building a fort in the woods create their own hideout where they can play away from adult supervision.
The word suggests secrecy and safety from unwanted discovery. A hideout is a place you can stay for a while, somewhere with enough space to settle in. A detective searching for a criminal tries to discover their hideout. During a game of manhunt, the best hideout is one where you can watch for searchers while staying completely hidden.
Hideouts appear throughout adventure stories because they represent that thrilling feeling of having your own secret space. Robin Hood had his hideout in Sherwood Forest. Pirates had hideouts on remote islands. Even superheroes sometimes need hideouts: the Batcave serves as Batman's secret headquarters beneath Wayne Manor.