Java and Bali to the east. Borneo lies to the north and Christmas Island is to the south. It is the world's 13th largest island. Java is surrounded by the Java Sea to the north, Sunda Strait to the west, the Indian Ocean to the south and Bali Strait and Madura Strait in the east. Java is almost entirely of volcanic origin; it contains thirty-eight mountains forming an east–west spine that have at one time or another been active volcanoes. The highest volcano in Java is Mount Semeru (). The most active volcano in Java and also in Indonesia is Mount
Battle of the Trench the Banu Qurayza tribe, leading to their surrender and enslavement or execution. The defeat caused the Meccans to lose their trade and much of their prestige. The battle is named after "trench", or "khandaq", that was dug by Muslims in preparation for the battle. The word "khandaq" () is the Arabised form of the Persian word "kandak" (meaning "that which has been dug"). Salman farsi the Persian advised Muhammad to dig a trench around the city. The battle is also referred to as the "Battle of Confederates" (). The Qur'an uses the term "confederates" () in sura "Al-Ahzab" to denote