Secret Passages were introduced Fortnite in Chapter 2 Season 2, giving players a new way to move around the map. Secret passages were tunnels that you would automatically pass through if you entered them, taking you to a different area. They were disguised as portable toilets and dumpsters, and if you interacted with them, you could jump inside, go through the tunnel, and exit somewhere else. If you learned the routes, they were an easy way to traverse areas and possibly get the drop on some enemies.
They were often centered around areas like the Cave and The Agency, and in newer seasons you could find them in places like the Fortilla, The Authority, and other places on the map.
Epic sent out a tweet earlier today to let them know that Secret Passages had been taken down, but they didn't explain why, saying it was "due to an issue." We don't know what this glitch was, or how it impacted players who went through the apparently buggy Secret Passages. Now that they no longer work as intended, the Secret Passage will simply function as hideouts instead, like their regular counterparts.
If you jump into one now, you'll end up hiding rather than traveling somewhere. This is bad news for people who like raiding Fortilla, Catty Corner and Authority vaults, as the secret passages gave you a great way out of the vault, as there were a lot of action outside. If you plan on getting all that sweet loot, make sure you have a solid exit plan.