This light is situated on the small island of Harmaja about six miles south of Helsinki and lying close to the main shipping channel into the harbour.  As its name suggests it is the front light of a range pair, the rear light being situated on top of the Lutheran Cathedral of Suomenlinna (qv).  Navigation aids of one sort or another have been situated on the island since the 1500s.  The present light was originally constructed in 1883 but, by 1900, it had become clear that it was too short for its intended purpose.  It was therefore substantially rebuilt.  This rebuild involved removing the lantern and replacing it with a round cast iron tower situated on top of the original, square stone tower.  What's not clear from the various sources I have searched is whether the current lantern is original or whether the lanter was actually replaced. 

The image below shows a panoramic view of the site with the Viking Lines Ferry, Mariella, about to pass the island at the start of her outward passage to Stockholm.