During the 1980s and 1990s, Yokkaichi was joined by Qingdao, China; Sochi, Russia; and Phnom Penh, Cambodia. In 2007, Mombasa, Kenya was added as currently the youngest Sister City relationship of Long Beach. During the years between 1963 and 2007, a variety of other cities around the globe pursued establishing Sister City relationships with Long Beach. Often facing diplomatic challenges and international tensions, some were successful, some were not. All were short-lived.