Suomenlinna Fortress: Helsinki’s best day-trip In 2025

Introduction

In June 2022, we made a two-week road trip through the Baltic States and ended our adventure with one day in Helsinki, Finland. As part of our Helsinki itinerary, we spent half a day exploring Suomenlinna, a sea fortress located just a short ferry ride from the city center but we would have loved to have more time there and make it a full day adventure,.

We had heard about Suomenlinna being one of Helsinki’s most unique and scenic places, and it truly lived up to the hype. The ferry ride itself was already a beautiful experience, offering views of the city skyline and the Baltic Sea. Once on the island, we found ourselves surrounded by coastal cliffs, old stone walls, hidden cafés, museums, and quiet residential streets.

If you too are planning a trip to Helsinki, then a day in Suomenlinna should absolutely be on your list.

Whether you’re into history, photography, coastal walks, or just want to escape the city noise for a few hours, this place delivers. Let’s dive into our full Suomenlinna travel guide and how to make the most of your visit.

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What is Suomenlinna?

Suomenlinna is an 18th-century sea fortress built across six linked islands, just off the coast of Helsinki. Originally constructed by the Swedes in 1748 to defend against Russian expansion, the fortress was known as Sveaborg—which means “Castle of the Swedes.” After Finland gained independence, the site was renamed Suomenlinna, meaning “Castle of Finland.”

Today, Suomenlinna is one of Finland’s most significant historical sites and has been recognized as a UNESCO World Heritage Site since 1991. But it’s much more than just a monument. It’s also a living village with about 800 residents, home to charming wooden houses, art studios, cafés, museums, and stunning nature trails.

With its mix of military history, seaside landscapes, and a relaxed, almost countryside feel, it’s a place where you can easily spend half a day or even a full one just wandering and enjoying the peaceful atmosphere.

How to Get to Suomenlinna

Getting to Suomenlinna couldn’t be easier—and it’s actually one of the most scenic parts of the whole experience.

The fortress is located just 15 minutes by ferry from Market Square (Kauppatori) in central Helsinki. The ferry is part of the HSL public transportation system, which means if you already have a day card or a valid ticket for public transport in Helsinki, the ferry ride is included at no extra cost.

Ferries run year-round, roughly every 20–30 minutes, and more frequently during summer. You’ll board a large, multi-deck boat that glides through the Baltic waters, offering great views of the Helsinki waterfront and nearby islands. If the weather’s good, grab a spot on the upper deck—it’s a beautiful start to your visit.

A quick note: there are also private “sea buses” at the same square, but those are more expensive and not included in the public transport ticket. Be sure to hop on the HSL ferry, which usually departs from the left side of the square if you’re facing the sea.

We recommend to rent a car through Discover Cars with free cancellation. Book your rental car here.

When to Visit

Suomenlinna is open all year, but each season offers a different experience:

• Summer (June–August): The most popular time to visit. Ferries run frequently, museums are open, and the island is full of life. Great for picnics, long walks, and sea views.
• Spring & Autumn (April–May, September–October): A bit quieter, but still very pleasant. Nature is either waking up or showing autumn colors. Some places may reduce hours, so check ahead.
• Winter (November–March): Peaceful and magical if you like solitude. The fortress can be covered in snow and fog. Ferries still run, but some museums are closed or open fewer hours.

Our recommendation: Visit during spring or summer if you want the full experience with open cafés, museums, and warmer walks along the shore.

Read: All our gears and equipments for hiking, blogging, vlogging and so much more…

What to Do in Suomenlinna

Walk the Fortress Walls

As soon as you arrive, head off along the main path toward the south of the island. Along the way, you’ll find grassy hills, stone bunkers, artillery cannons, and stunning sea views. You can follow the marked Blue Route which connects the main sights, but feel free to wander off the path a little—the entire island is made for exploring.

Climbing the fortress walls gives you a sense of the site’s strategic importance, but also offers the best panoramic views of the Gulf of Finland. It’s peaceful, a bit wild, and feels completely different from the city you just came from.

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Visit the King’s Gate

The King’s Gate is one of the most iconic spots on the island. It’s a beautiful archway located on the island’s east side, marking the old entrance to the fortress. It was originally built in the 18th century and is still a powerful symbol of the island’s military past. The gate is a great spot for photos, and the views of the harbor from here are stunning.

We usually travel with Airalo eSIMs, but when we need unlimited data for work, we go with Holafly.

Check Out the Suomenlinna Museum

To truly understand the history of the fortress, make time for the Suomenlinna Museum, which offers exhibits on the military history, construction, and historical significance of the fortress. The museum is housed in one of the original fortress buildings, so you get a sense of the old-world charm mixed with educational displays.

Inside, you’ll learn about the Russian and Swedish military presence in the area, the island’s role during the wars, and how it transitioned into a UNESCO World Heritage site. It’s a great stop to deepen your appreciation of the place before continuing your explorations.

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Take a Picnic Break at the Small Beaches

One of the things we loved most about Suomenlinna was its relaxed atmosphere. In fact, if you’re on the island for a few hours, pack a snack or lunch and enjoy a picnic by one of its small beaches. Several sandy spots along the island are perfect for just sitting back and watching the waves. The Seahorse Beach near the southern tip is a popular spot for locals and has a beautiful setting by the water.

It’s also a nice place to rest after walking along the fortress walls—just enjoy the sounds of the sea and the occasional ferry passing by.

Explore the Submarine Vesikko

If you’re interested in something more interactive, the Submarine Vesikko is a must-see. This 1930s submarine has been fully restored, and you can climb aboard to see what life was like aboard a war vessel. The tight corridors, original equipment, and military history make it a fascinating stop, especially if you’ve never been inside a submarine before.

Tip: We never travel without our DJI Mini 3 PRO drone anymore — it’s totally worth having to capture places from a whole new perspective.

Stop by the Brewery

Suomenlinna isn’t just about history and nature—it’s also home to a few modern touches, like the Suomenlinna Brewery. This craft brewery is a great place to stop for a cold drink after a day of sightseeing. It’s set in a historic building, so the atmosphere is a unique mix of traditional and contemporary. The brewery often serves a variety of locally crafted beers, and there’s a nice outdoor seating area where you can relax with a drink and enjoy the island’s peaceful vibes.

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Explore the Shops and Cafes

As you walk around, you’ll come across several charming cafes and small shops that sell local crafts, souvenirs, and snacks. Café Vanille, located near the ferry terminal, is a popular spot for a coffee or cake while you soak in the sea views. There’s also a small gift shop near the Suomenlinna Museum, where you can pick up something special to remember your visit.

Tip: We hike with Osprey backpacks and can’t recommend them enough — the Talon 44 and Tempest 40 are comfortable, durable, and great for any adventure.

Visit the Ehrensvärd Museum

Located on the island’s southern tip, the Ehrensvärd Museum is housed in the former home of Augustin Ehrensvärd, the founder of the fortress. The museum offers a glimpse into the personal life of the man who built the fortress and provides additional historical context about the island. The museum’s antique furniture and personal belongings create a nice contrast with the military history surrounding the island.

We usually travel with Airalo eSIMs, but when we need unlimited data for work, we go with Holafly.

Take a Guided Tour

If you want a more in-depth look at Suomenlinna, consider joining a guided tour. There are several available, including walking tours that focus on the fortress’s military history or the natural history of the island. A guide can help bring the history of the island to life, and they often share fun facts and stories that you might not hear otherwise. Plus, it’s a great way to ensure you don’t miss any of the main sights.

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Enjoy the Quiet and Nature

Even if you aren’t much of a history buff, Suomenlinna is a great place to unwind. The island has a serene atmosphere, with lots of green space and scenic walking paths. You can take a leisurely stroll along the coast, enjoy the wildflowers in the fields, or just sit on a bench and listen to the sound of the sea. It’s an ideal place to take a break from the bustle of city life and connect with nature.

Tip: We never travel without our DJI Mini 3 PRO drone anymore — it’s totally worth having to capture places from a whole new perspective.

Tips for Visiting Suomenlinna:

• Wear comfortable shoes: The island has a lot of cobblestone paths and grassy areas, so comfortable shoes are a must.
• Take a ferry: If you’re staying in Helsinki, the ferry ride to and from the island is beautiful, and it’s included in the public transport system.
• Check ferry schedules: The ferry service runs frequently, but it’s always good to check the times in advance, especially in the off-season.
• Pack water and snacks: There are cafes on the island, but if you’re planning to explore all day, bringing your own supplies is a good idea.
• Bring a camera: There are so many photo-worthy spots on the island—from the historic buildings to the beautiful landscapes, you’ll want to capture it all.

Tip: We use the DJI Action 4 to film our vlogs — compact, durable, and perfect for capturing every adventure.

Final Thoughts

Suomenlinna is a fantastic day trip from Helsinki, offering a mix of history, nature, and stunning views. Whether you’re interested in exploring the fortress, relaxing by the sea, or simply taking in the scenery, you’ll find something to love here. With so much to do, it’s easy to spend an entire day—or more—on this charming island.

Where to Stay

We made a 1-day trip to Helsinki, but honestly, this city has so much to offer that you could easily stay for one or two more nights and enjoy it at a slower pace. Whether you’re into Nordic design, cozy cafés, seaside views, or modern architecture—Helsinki has it all. Here are a few great accommodation options for every budget:

• (€) Citybox Helsinki: A stylish, budget-friendly hotel right in the heart of Helsinki. Clean, modern, and functional—perfect if you just need a comfortable place to rest between sightseeing. Self check-in makes it super easy for short stays.
• (€€) Solo Sokos Hotel Helsinki: Located just steps from Senate Square, this centrally located hotel is a great mid-range option. Rooms are cozy yet elegant, and the breakfast buffet is a highlight.
• (€€€) Lapland Hotels Bulevardi: If you’re looking for a touch of luxury and a unique Nordic vibe, this hotel delivers. Inspired by Lapland’s natural beauty, it features beautiful design, spa-like bathrooms, and a calm atmosphere in one of the city’s most charming districts.

For a Unique Stay: Want something different? You can also book a night cruise and sleep on a ship. Some ferries between Helsinki and Stockholm or Helsinki and Tallinn offer overnight routes with cabins. It’s a fun way to combine transport and accommodation in one unforgettable experience.

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