The Suomenlinna sea fortress is a UNESCO World Heritage Site. Built over a period of three centuries, Suomenlinna is nowadays a unique residential district of Helsinki and a popular tourist destination.

In 1991, the fortress was added to the UNESCO World Heritage List as a unique monument of military architecture. One of the features that distinguishes the fortress is the role it has played in the defence of three different states: Sweden, Russia and Finland.

The fortress is a versatile destination for visitors, offering things to see and do in all seasons. Suomenlinna has excellent services, and events are organised all year round. Check the opening hours of services and event times before your visit.

Suomenlinna is always open, and there is no entrance fee to the fortress. The fortress features fascinating sights, old stone walls, artillery and beautiful parks.

Suomenlinna is also a neighbourhood of Helsinki with about 800 residents. The island has many local services, including a grocery store, library, comprehensive school, day care centre, and church.