The Opium wars were started due to the merchandize of Opium in Guangzhou and also Guangdong became the most important port for manual laborers who finally settled in British Malaya, Canada, America, Dutch Indies (now known as Indonesia), Siam (now known as Thailand) and the British Crowne Colony of Singapore. The Province of Guangdong has a total of 4300 km coast. At the southwest of the province is the Lei Zhou Peninsula which has until today still a few inactive volcanoes. The Pearl River delta is made up of hundred's of little islands. In the summer months, Guangdong Province has a very hot and humid climate but the good news is that winters are very short.