Flat Brook
Flatbrook is an tributary of the Delaware River in Sussex County, New Jersey in the United States. Upstream of the inflow of Little Flatbrook, the brook is known as Big Flatbrook. Historically, the watershed of the Flatbrook, and its two main tributaries, the Little Flatbrook and Big Flatbrook, has been known as the "Walpack Valley" and is part of the historic Minisink region. The Appalachian Trail passes through the watershed of the Flatbrook along Kittatinny Mountain. The Flat Brook flows into the Delaware River near Walpack Bend in the Flatbrookville section of Walpack Township.