Perho is a municipality of Finland. It is located in the province of Western Finland and is part of the Central Ostrobothnia region. The distance between Perho and the regional center Kokkola is about 100 kilometres (62 mi). The municipality has a population of 2,578 and covers an area of 775.19 square kilometres (299.30 sq mi) of which 27.25 km2 (10.52 sq mi) is water. The population density is 3.45 inhabitants per square kilometre (8.9/sq mi).

Alajärvi is a town and municipality of Finland. It is located in the South Ostrobothnia region. The town has a population of 9,113 and covers an area of 1,056.74 square kilometres (408.01 sq mi) of which 47.99 km2 (18.53 sq mi) is water. The population density is 9.03 inhabitants per square kilometre (23.4/sq mi). The town is unilingually Finnish; there are few immigrants.