Singapore consists of 63 islands, including the main island, widely known as Singapore Island but also as Pulau Ujong. There are two man-made connections to Johor, Malaysia: the Johor–Singapore Causeway in the north, and the Tuas Second Link in the west. Jurong Island, Pulau Tekong, Pulau Ubin and Sentosa are the largest of Singapore’s smaller islands. The highest natural point is Bukit Timah Hill at 166 m (545 ft).
There are ongoing land reclamation projects, which have increased Singapore’s land area from 581.5 km2 (224.5 sq mi) in the 1960s to 716.1 km2 (276.5 sq mi) today; it may grow by another 100 km2 (40 sq mi) by 2030. Some projects involve merging smaller islands through land reclamation to form larger, more functional islands, as with Jurong Island. 5% of Singapore’s land is set aside as nature reserves. Urbanisation has eliminated most primary rainforest onthe main island, Bukit Timah Nature Reserve being the only significant remaining forest. There are only about 250 acres (101 ha) of farmland remaining in Singapore.
Singapore has a tropical rainforest climate (Köppen: Af ) with no distinctive seasons, uniform temperature and pressure, high humidity, and abundant rainfall. Temperatures usually range from 22 to 35 °C (72 to 95 °F). Relative humidity averages around 79% in the morning and 73% in the afternoon. April and May are the hottest months, with the wetter monsoon season from November to January. From July to October, there is often haze caused by bush fires in neighbouring Indonesia. Although Singapore does not observe daylight saving time, it follows time zone GMT+8, one hour ahead of its geographical location.
Singapore’s main territory is a diamond-shaped island, although its territory includes surrounding smaller islands. The farthest outlying island is Pedra Branca. Singapore is slightly more than 3.5 times the size of Washington, D.C. Of Singapore’s dozens of smaller islands, Jurong Island, Pulau Tekong, Pulau Ubin and Sentosa are the larger ones. Most of Singapore is no more than 15 meters above sea level.
The highest point of Singapore is Bukit Timah, 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. Singapore has no natural lakes, but reservoirs and water catchment areas have been constructed to store fresh water for Singapore’s water supply.
Singapore has reclaimed land with earth obtained from its own hills, the seabed, and neighbouring countries. As a result, Singapore’s land area has grown from 581.5 km² in the 1960s to 723.2 km² today, and may grow by another 100 km² by 2033.