oulun + kylä, of unclear origin (not directly related to Oulu). The name may originate as an adaptation of the Swedish name Åggelby, perhaps from å(“river”) + göl(“pool, lagoon”), gärde(“fenced field”) or kulla(“hill”) + by(“village”). However, the name may also be of Finnish origin and be related to the name of the village Ohkola in Mäntsälä, although the phonological development appears difficult to reconcile.[1] Yet a third theory even suggests that it derives from oulu, the same word as Oulu, but this is unlikely, given that evidence for the name containing plosives -g- stretches back centuries and due to the distribution of oulu (Lapland and Northern Ostrobothnia).