Pulau Ujong (Malay: literally 'island at the end'), also known as Singapore Island or Mainland Singapore, is the main constituent island of Singapore. It is part of the Malay Archipelago and is located at the tip of Peninsular Malaysia. The island forms the majority of the country in terms of area and population as citizens are unable to reside in smaller islands of Singapore. With a population of 5,469,700 and an area of 710 square kilometres, Pulau Ujong is the 21st most populous island in the world and the 31st most densely populated island in the world.
Pulau Ujong was the earliest reference to Singapore Island. The 3rd-century Chinese reference to Po Lo Chung (蒲羅中) corresponds to the Malay reference known as Pulau Ujong. Travellers from the Straits of Malacca to the South China Sea would have to pass through[clarification needed] the island, hence the name Pulau Ujong. Like Johor's old name, Ujong Tanah meaning "Land's End", the island was known better by the Orang laut as Pulau Ujong literally meaning "End Island". Ujong Tanah or its variants were also used in European sources as a name for Singapore.
According to a third-century book Record of Foreign countries during the Eastern Wu Period (吴时外国传), Pu Luo Jong (Pulao Ujong) was inhabited by cannibals with five to six inch tails.
The island measures 50 kilometres (31 mi) from east to west and 26 kilometres (16 mi) from north to south with 193 kilometres (120 mi) of coastline. The highest point of Singapore is Bukit Timah Hill, with a height of 165 m (538 ft) and made up of igneous rock, granite. Hills and valleys of sedimentary rock dominate the northwest, while the eastern region consists of sandy and flatter land. Since 1822, there were land reclamation works by British, who at that time controlled the island and the government of Singapore has continued to increase the size of the island after independence, which increased the area of the island from 580 km2 (224 sq mi) in the 1960s to 710 km2 (274 sq mi) today.