Somero (Finnish pronunciation: [ˈsomero]) is a municipality of Finland, located in the province of Western Finland and part of the Finland Proper region. The municipality has a population of 9,174 (30 November 2014) and covers an area of 697.68 square kilometres (269.38 sq mi) of which 29.9 km² (11.5 sq mi) is water. The population density is 13.74 inhabitants per square kilometre (35.6/sq mi).