兀兰
The Port of Singapore is not a mere economic boon, but an economic necessity because Singapore is lacking in land and natural resources. The Port is critical for importing natural resources, and then later re-exporting products after they have been refined and shaped in some manner, for example wafer fabrication or oil refining to generate revenue. The service industries such as hospitality services typical of a port of call restock the food and water supplies on ships. Ships pass between the Indian Ocean and the Pacific Ocean through the Singapore Strait. The Straits of Johor on the country's north are impassable for ships due to the Johor-Singapore Causeway, built in 1923, which links the town of Woodlands, Singapore to the city of Johor Bahru in Malaysia.