Perth Amboy is a city in Middlesex County, New Jersey, United States. As of the United States 2000 Census, the city population was 47,303. Perth Amboy is known as the "City by the Bay". Perth Amboy was formed by Royal Charter on August 4, 1718, within various townships. Perth Amboy was chartered as a city by an Act of the New Jersey Legislature on December 21, 1784, within Perth Amboy Township and from part of Woodbridge Township. Perth Amboy Township was formed on October 31, 1693, and was enlarged during the 1720s to encompass Perth Amboy city. Perth Amboy Township was incorporated as one of New Jersey's initial 104 townships on February 21, 1798. The township was absorbed by Perth Amboy city on April 8, 1844. Perth Amboy, and South Amboy across the Raritan River, are collectively referred to as The Amboys. Signage for Exit 11 on the New Jersey Turnpike refers to "The Amboys" as a destination. The Amboys are the northern limit of the area informally referred to as the Bayshore.