Flatbrookville is an unincorporated community located along Old Mine Road within Walpack Township, in Sussex County, in the U.S. state of New Jersey.

[2] It is named after the Flat Brook, a tributary of the Delaware River, which flows through the community.

[4] The Decker Ferry House, built c. 1800, and the Rosenkrans Ferry House, also known as the Smith-Rosenkrans House, built c. 1807, provided ferry service across the Delaware River at the Walpack Bend.

Both are contributing properties of the Old Mine Road Historic District.

This Sussex County, New Jersey state location article is a stub.