Treehouse

"HYDRAS on the offensive. They've taken the Treehouse and Mile one and those are just the ones we know of."

- Blake Staley to Jack Scrivens

The Treehouse is a L.A.S.E.D. Facility that was overrun by HYDRA

History
When HYDRAs existence inside of the FBI and other branches of government were revealed HYDRA went on the offensive, purging their facilities of all non HYDRA members and attacking other bases. A HYDRA faction attacked the treehouse and managed to take control of it.