The Township of Branchburg is located in Somerset County, New Jersey.  The Township includes the communities of North Branch and Neshanic Station.  It is bordered on the west by Hunterdon County, on the north by Bedminster and on the south by Bridgewater Township and Hillsborough Township.  Branchburg covers a total area of 20.2 square miles, being eleven miles long and approximately 2 miles across at its widest point.  The main water courses are the Lamington River on the north, the North Branch of the Raritan River on the east and the South Branch of the Raritan River on the east and south.

The land now known as Branchburg Township was originally inhabited by the Raritan Indians, a tribe of the Lenni-Lenape Indians.  By 1686 most of the land was purchased from the Indians by the Lords Proprietors of East Jersey.  These Proprietors sold the land in small parcels to numerous settlers, mostly of Dutch or English extraction.  Branchburg at that time was located in a large area called East Jersey, but more specifically, it encompassed parts of Essex and Middlesex Counties as well as Somerset County.  County boundaries were a subject of controversy until 1741 when Somerset County acquired parts of Middlesex and Essex Counties, nearly doubling it's size.  Due to the expansion of Somerset County, Branchburg finally lay entirely within the County where it is presently located.

Today, Branchburg Township is a semi-rural area.  A strict zoning plan has been actively enforced since 1948.  The zoning ordinance provides for residential, business, industrial, office, manufacturing, office building and office laboratory uses.  There is a touch of a small village flavor in North Branch and Neshanic Station.

Branchburg is also a college town, the home of Raritan Valley Community College with 250 acre campus and nearly 5,000 full and part-time students.

State Highways 202 and 22 run through Branchburg as well as County Route 28 in North Branch. With a stop at the Municipal Park-and-Ride facility on US Highway 202 North, bus service between Branchburg and New York City on the Trans-Bridge bus line is available on a daily basis.  (Please note that parking permits are required to park in the Park & Ride Lot).  New Jersey Transit, Raritan Valley Line has  service from North Branch Station to Newark.  In Newark, connections can be made to New York City.  Newark International Airport is located approximately 35 miles northeast of Branchburg.  Also within driving distance are Allentown-Bethlehem-Easton Airport (ABE) in Pennsylvania and Kennedy International and La Guardia Airports in New York, as well as the Mercer Airport near Trenton and Princeton.