Bertrand Island is a small peninsula in Lake Hopatcong in Mount Arlington, New Jersey, long associated with recreation and tourism. Best known as the site of Bertrand Island Amusement Park, it evolved from a picnic ground before World War I into a popular destination that peaked in 1925 with rides, a roller coaster, and boardwalk games. Its success reflected Lake Hopatcong’s broader tourist economy, which declined during the Great Depression and after the 1938 collapse of the lake’s ice industry. The island was also the birthplace of Miss America 1937 Bette Cooper. Now largely residential, it remains closely identified with its amusement park past.