context: King Gustav Vasa founded Forsby, the medieval village of Koskela, on the mouth of the Vantaanjoki River in Helsinki, June 12, 1550, mainly to compete with Tallinn on the other side of the bay. The day has since begun to be celebrated on Helsinki Day. Residents were captured when the bourgeoisie of the cities of Porvoo, Ekenäs, Rauma and Ulvila were ordered to move to a new city. [8]
question: When was Helsinki Founded?
answers.text: June 12, 1550