Union County is one of the minor bedroom communities for New York City. Union County also has diverse working class communities in places like Plainfield and Elizabeth. Somerset County also serves as a bedroom community for New York City, though there is a strong local economy centered around the pharmaceutical and technology industries. Hunterdon County is also the wealthiest county in New Jersey, as measured by per-capita income. Hunterdon County—ranked at #3 per capita—has a strong local industry while also to a lesser extent serving as a bedroom community for New York City. Warren County serves as an exurban community for New York City. The area code also covers the cities of Elizabeth and Linden among other municipalities along New Jersey's "Refinery Row."