Watchung is a borough in Somerset County, New Jersey, United States. It is located within the Raritan Valley region. The name "Watchung" comes from the Lenni Lenape Native Americans, meaning "high hills”. The borough borders Green Brook Township, North Plainfield and Warren Township in Somerset County; and Berkeley Heights, Plainfield, and Scotch Plains in Union County. The Stony Brook flows through Watchung borough, making its way from Warren Township to the Watchung Lake, then through the gorge in the first Watchung mountain and over the Wetumpka Falls, on its way to the Green Brook. The borough is roughly a 40-minute drive from New York City and a 20-minute drive from Newark.