Avalon is a borough in Cape May County, in the U.S. state of New Jersey. It is located on Seven Mile Island. As of the 2020 United States census, the borough's population was 1,243, a decrease of 91 (−6.8%) from the 2010 census count of 1,334, which in turn declined by 809 (−37.8%) from the 2,143 counted in the 2000 census. The borough's population swells to as many as 45,000 during the summer.

Cape May County is the southernmost county in the U.S. state of New Jersey. Much of the county is located on the Cape May peninsula, bound by the Delaware Bay to its west and the Atlantic Ocean to its south and east. Adjacent to the Atlantic coastline are five barrier islands that have been built up as seaside resorts. A consistently popular summer destination with 30 miles (48 km) of beaches, Cape May County attracts vacationers from New Jersey and surrounding states, with the summer population exceeding 750,000. Tourism generates annual revenues of about $6.6 billion as of 2018, making it the county's single largest industry. The associated leisure and hospitality industries are Cape May's largest employers. Its county seat is the Cape May Court House section of Middle Township. The county is part of the Jersey Shore region of the state.