Surabaya is the capital and largest city of East Java, Indonesia, located in the east of Java Island and southwest of Surabaya Strait on the northeast coast. It is the second largest seaport and city in Indonesia and an important commercial and industrial center. Surabaya has been a foreign trade port of Java since the Middle Ages and is still a busy port city. The population of Surabaya is about 3.5 million, including about 500,000 Chinese. The original meaning of the name Surabaya in Javanese is shark and crocodile. This area used to be a swamp. For the convenience of pronunciation, China people homonymized it as "Surabaya" and later changed it to the authentic name of the Chinese character "Surabaya".