Brumevale, mentioned in Nightfall, is one of the Black Swan's hideouts. This is the location in which Sophie learns that one of the two people who played Mr. Forkle is still alive. This is the only place Mr. Forkle has found Moonlarks in the wild. The place is said to be ancient, having a complicated history, only to be reclaimed by the Black Swan. Brumevale is the location where Project Moonlark was conceived.
Much like Atlantis, to access Brumevale, you must first light leap to a place that is described as a hot, humid place with thick swirls of white fog fuzzing out any glimmer of the sky. It is said to feel like the center of a cloud, or the "inside of a verminion's cheeks", as dubbed by Keefe. In Nightfall, it is shown that Tiergan releases a whirlwind, giving them clarity to climb and revealing a staircase leading up to a lighthouse.
The staircase to enter Brumevale consists of narrow blue stones that hovered in the sky, without any anchor, railing, or structure. The staircase is said to be the only way in or out of the hideout. At the top, there is a lighthouse sprouted straight out of the sky which seems to emit a deep, soulful hum. Inside the lighthouse is a weathered door carved from rich, cherry colored wood, which leads to a small, round chamber. The room is decorated with shabby armchairs and faded rugs, and has a narrow staircase tucked in the shadows that leads upstairs.