What's In A Name?
The name "Middlebrook" is derived from a stream that flows through the Washington Valley and the Watchung Mountains at Chimney Rock. A small village of the same name was located at the junction of that creek and the Raritan River.
Middlebrook can no longer be found on any modern maps and was eventually integrated into the town of Bound Brook. The entire Middlebrook encampment area included sections of Bridgewater Township, Pluckemin, Bound Brook, and Martinsville.
General Washington identified his correspondence with the name "Middlebrook" during the times he stayed there.