The Dutch Hill Mansion was a mansion located on Dutch Hill in Brooklyn. As a boy Eddie Dean was fearful to enter the house as it had a reputation that matched that of The Marsten House mentioned in Salem's Lot. Jake Chambers had to enter the Mansion and face the demon inside to get to Mid-World the second time.
Connection between Dutch Hill Mansion and House on Neibolt street (IT)
There appears to be a connection between the Dutch Hill Mansion and the house on Neibolt Street from It. During the events of this novel, the Ka-tet of children from Derry seeking to confront the eponymous creature travel to the house on Neibolt. Inside the house they see wallpaper which has elves with green caps and roses in a long hallway, the same wallpaper that Jake sees inside the Dutch Hill Mansion. The whole insides of both houses change in shape and move around: in the house on Neibolt when It appears, and in Dutch Hill Mansion when Jake has to face the demon guarding the portal to Mid-World.