Little Flat Brook is a 12.7-mile-long (20.4 km) [1] tributary of Flat Brook in Sussex County, New Jersey in the United States. [2]
Upstream of the confluence with Little Flat Brook, Flat Brook is known as Big Flat Brook. [2]
41°11′33″N 74°50′41″W / 41.19238°N 74.844747°W