Just a short ferry ride (15-20 mins) from the heart of Helsinki lies Suomenlinna, a historic sea fortress spread across several islands which is a UNESCO World Heritage Site and one of Helsinki’s most iconic and treasured landmarks. This sea fortress, built across six interconnected islands, offers visitors a unique blend of history, architecture, and natural beauty. Whether you’re a history enthusiast, a nature lover, or simply looking for a peaceful escape from the city, Suomenlinna is a must-visit destination for anyone traveling to Helsinki.

A Brief History of Suomenlinna

Suomenlinna’s history dates back to the mid-18th century when Sweden began constructing the fortress to defend against Russian expansion. Originally named Sveaborg (Fortress of Sweden), it was a critical military outpost due to its strategic location in the Gulf of Finland. Over the centuries, it has witnessed several key moments in Nordic history, from battles between Sweden and Russia to its role during the Crimean War.

In 1808, the fortress was surrendered to Russian forces, and Finland later became an autonomous part of the Russian Empire. It was during this period that the name was changed to Suomenlinna (Fortress of Finland). Today, the island serves as a reminder of the region’s complex history, representing both Swedish and Russian influences, while remaining a symbol of Finnish resilience and independence.

Exploring Suomenlinna: Top Attractions and Landmarks

Suomenlinna is more than just a fortress — it’s a vibrant area with museums, walking trails, restaurants, and even a small residential community. Here are some must-see attractions during your visit:

A. The Great Courtyard (Suuri Linnapiha)

At the heart of Suomenlinna is the Great Courtyard, the main square of the fortress. Built in the 18th century, this impressive space is surrounded by historic buildings, including the Ehrensvärd Museum, dedicated to the fortress’s founder, Augustin Ehrensvärd. Here, you can learn more about the early days of Suomenlinna and the life of its Swedish founder.

B. Suomenlinna Church

Originally constructed as an Eastern Orthodox church during Russian rule, the Suomenlinna Church was later converted into a Lutheran church. Its neoclassical architecture stands as a testament to the island’s layered history, and it features a unique lighthouse on top of its tower, still in use today to guide ships navigating the nearby waters.

C. The King’s Gate

One of the most recognizable landmarks on the island, The King’s Gate was built in the mid-18th century to serve as the ceremonial entrance to the fortress. It’s a popular spot for photography, offering stunning views of the surrounding sea and archipelago. Visitors often walk along the defensive walls here, imagining what life must have been like for the soldiers stationed on the island centuries ago.

D. Suomenlinna Museum

For those who want to dive deeper into the history of the fortress, the Suomenlinna Museum provides an excellent overview of the site’s military and cultural significance. The exhibits span from the fortress’s Swedish origins to its role in both world wars, offering insights into the everyday life of soldiers and civilians who lived on the island. To avoid long queues and waiting, you can buy ticket online here- Helsinki: Suomenlinna Museum Ticket.

E. The Submarine Vesikko

Another fascinating stop is the Submarine Vesikko, a World War II-era Finnish submarine now serving as a museum. Visitors can step inside the vessel to get a glimpse of what life was like aboard this compact and highly functional military craft. Vesikko is one of the few surviving submarines from that era, making it a unique attraction for military history buffs.

F. Bastion Zander

The way to Bastian Zander at Kustaanmiekka, in southern Suomenlinna, has been the flag bastion of the fortress throughout its history. It is my favourite route over the walls of the fortress walking by the sea view and in this route if you’re lucky, you can catch best sunset view as well.

The bastion was built between 1748 and 1750 as part of a chain of four bastions. The walls of the bastion comprise mainly vertical rock faces with a low parapet on top which has 14 embrasures in it.

Highlights

I. Nature and Scenic Walks- While Suomenlinna is steeped in history, it also offers plenty of opportunities to enjoy the island’s natural beauty. The island’s walking trails wind through grassy hills, along the rocky shorelines, and past old cannons and fortifications, making it an ideal destination for a leisurely hike.

II. The Southern Shoreline- The southern part of Suomenlinna offers some of the most picturesque views of the surrounding archipelago and the open sea. The rocky cliffs and coastal paths here provide a serene contrast to the fortress’s military structures. It’s a peaceful area where you can sit by the water and watch ferries and boats pass by in the distance.

How to Get to Suomenlinna

Getting to Suomenlinna is easy and part of the experience. The fortress island is accessible year-round by a ferry that departs from Helsinki’s Market Square (Kauppatori). The 15-minute ferry ride offers lovely views of the city’s waterfront, and during the summer months, additional boat services provide even more options for visiting the island. If you’re on a day trip to Helsinki or short on time then you can also take a 5 hours guided tour of Helsinki which covers major touristic attractions in Helsinki including Suomenlinna island. Here is your recommended guided tour- Helsinki: City and Suomenlinna 5-Hour Sightseeing Tour.

Dining and Staying on the Island

While exploring Suomenlinna, there are several cafes and restaurants offering local Finnish cuisine and refreshments. Whether you’re in the mood for a quick snack or a sit-down meal, you’ll find plenty of options to satisfy your appetite.

For those who wish to extend their stay, Suomenlinna offers a few accommodation options, including hostels and guesthouses, giving visitors the chance to experience the tranquility of the island after the day-trippers have gone. Though there are many cheap hostels and hotel accommodation in Helsinki near the port area which is 20-25 mins distance overall, therefore I personally recommend them if you’re on a budget travel.

Conclusion

Suomenlinna is much more than a historic fortress — it’s a living, breathing part of Finland’s heritage that combines history, culture, and nature. Whether you’re wandering through its centuries-old fortifications, exploring its museums, or simply enjoying the scenic beauty of its islands, Suomenlinna offers an unforgettable experience just minutes away from Helsinki.

So, hop on a ferry, step back in time, and let the magic of Suomenlinna transport you through history while immersing you in Finland’s natural beauty.