Madura Strait is a stretch of water that separates the Indonesian islands of Java and Madura, in the province of East Java. The islands of Kambing, Giliraja, Genteng, and Ketapang lie in the Strait. The Suramadu Bridge, the longest in Indonesia, spans the strait between Surabaya on Java and Bangkalan on Madura.

Java is one of the Greater Sunda Islands in Indonesia. It is bordered by the Indian Ocean to the south and the Java Sea to the north. With a population of 151.6 million people, Java is the world's most populous island, home to approximately 56% of the Indonesian population. Indonesia's capital city, Jakarta, is on Java's northwestern coast.