Lantau Island and the majority of the remaining islands are part of the New Territories, an area that also encompasses the hilly terrain north of Kowloon. Hong Kong Island is separated from Kowloon by Victoria Harbour, a natural landform harbour. The Kowloon Peninsula to the south of Boundary Street and the New Territories to the north of Hong Kong Island were added to Colonial Hong Kong in 1860 and 1898, respectively.