We walked along the narrow wooden jetty towards the forest in deliberate silence. The sky was pastel grey, but the day felt mild. A fresh breeze skimmed off the Baltic, brushing the tops of the pine trees. Listening mindfully, I realised how incredibly satisfying I found the sound of the dry spindly needles and chunky cones crunching underfoot.

“I like starting nature hikes quietly, to help us become instantly connected with our surroundings,” said my local nature guide, Simo Peri, tying up his shoulder-length blond hair as we walked. On his back, a pack containing a surprising number of supplies for our half-day adventure, as I would realise later.

“It’s so easy to just start chatting or taking pictures that we don’t notice what’s going on around us,” he explained. “Seals also have incredible hearing and I’m hoping we’ll spot some.”

I was in the unsung Eastern Gulf of Finland National Park, a serene area in south-eastern Finland, that tourists often overlook in favour of the western archipelago. I was also fresh from a highly invigorating 45-minute RIB water taxi ride across the inky-black Baltic from Sapokka harbour at Kotka. This port and industrial city is two hours east of Helsinki, and acts as the gateway to Finland’s south-east. I was on an otherworldly uninhabited island called Ulko-Tammio, 10km from the Russian border, and nearly completely covered by forest except for the shoreline.

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It’s been dubbed the country’s first “phone-free” island, as part of a campaign to encourage visitors to put their phones away and experience it with all their senses. There are 100 islands and islets in the Eastern Gulf, but Ulko-Tammio is one of the most unspoiled and beautiful. No one has ever lived here, Simo told me later over lunch around the campfire, and that’s what gives it a unique atmosphere. “It’s only been used as a fishermen’s camp and a pasture for people from other islands, like nearby Tammio. It’s also easy to hike around, a habitat for rare birds. You can freely pick berries, and edible mushrooms, camp out and light fires,” he said.

Eventually, we emerged into the open, onto huge slabs of grey-red granite lapped by the Baltic. I felt like I’d landed on another planet, or time-travelled to a prehistoric age on earth. There was no one else around. “We call this rapakivi,” Simo pronounced, with a pleasing Finnish roll of the letter ‘r’. What a great word, I thought, as he looked down, lightly tapping the ground with a hiking shoe-clad foot.

I looked down too, and took in the beauty of this billion-year-old-plus geology, the bedrock of Ulko-Tammio. “Here,” he said, handing me a delicate, grass-like blade. “I think you call them chives?” Sure enough, it tasted just like a chive. Its discovery had completely distracted me from the fact we hadn’t yet spotted a seal – and, for that matter, the fact I hadn’t touched my phone since my arrival. “They know better than to hang about on rocks catching a cold,” said Simo of the former. “They’re probably out diving for fish, keeping warm somewhere.”

My introduction to Finland’s peaceful eastern archipelago had started in a glass cabin at the Santalahti Resort in Kotka the previous night. As well as hiking the paths around the resort, I spent hours at the fascinating Maritime Centre Vellamo in town, where I learned about the area’s relationship to water and the weather – and icebreakers. These giant vessels clear the shipping lanes in winter, and are a vestige of Finland’s long tradition of shipbuilding. I dined like a local on Varissaari – “restaurant island”, as it is known – home to the Vaakku Summer Restaurant, a 10-minute ferry ride from Kotka harbour, followed by a traditional Finnish nightcap: a sundowner session in Santalahti’s dreamy outdoor glass sauna, before a swift dip in the Baltic.

On Ulko-Tammio, away from the shore, the island interior felt mysterious and otherworldly. The air was cool and moist, and a carpet of glistening elkhorn and reindeer lichen covered the forest floor – along with, to my surprise, wild strawberries, my favourite fruit. They’re so much smaller than I’d imagined: delicate, ruby-hued miniatures of what we’re used to in England. Automatically, I reached for my phone but just as quickly stopped myself. Instead, I focused on savouring the unusual earthy-sweet flavour and juicy texture.

In contrast to Ulko-Tammio’s wild innocence, wartime remnants such as cannons, gun emplacements and ammunition stores are haunting reminders of its role in the Second World War as a guard post on the eastern border of Finland. There’s also an eerie 70-metre-long cave built to protect personnel, which we walked through in almost complete darkness to get to the other side.

Towards the end of our loop walk in and out of the forest, at the top of the wooden bird-watching tower – the highest point on the island – the sun emerged in full force. From here, you get a 360-degree view across the island, and – in good weather – of the distant islands of Bolshoi Tyuters, Gogland and Sommer, which belong to Russia and lie just 10km away. A stroll past a traditional red hut, complete with beds and a kitchen, that visitors can stay overnight in, and we’re at the end of our nature walk.

“You can’t be unhappy if you have marshmallows,” said Simo at this point, taking out all manner of snacks and cooking equipment ready for lunch: two Bialetti coffee pots, two small gas cookers, two packets of sausages, cups and plates. He sawed some wood, swiftly made a fire and served us up barbecued sausages, which we topped with Sinappi, hot Finnish mustard, squeezed from a metal tube.

“I used to be a chef in Helsinki,” he told me, carving points on the ends of two sticks with a big knife from his leather case. “One day I realised I wanted to step away from the high-pressure environment. We were cooking great food, and getting great reviews, but I knew I wanted to change things, so I started to investigate how I could work more in nature, and here I am.” He stopped talking and stabbed a chunky marshmallow onto the end of a carved stick and held it over the crackling fire.

My last night is spent on Kaunissaari, an inhabited island peppered with traditional red Finnish summer cabins – and home to just one hotel, Hotelli Maja, open in the summer months. The island is also well known for its big bowls of salmon soup; I sampled a big pot of the steaming, delicate clear broth filled with chunks of fresh fish and flavoured with fragrant dill at the hotel’s restaurant and wasn’t disappointed. It was the perfect meal after a cycle through the Kaunissaari forest to the lighthouse on the island’s northern edge. Here, I surprised myself; after my experience on Ulko-Tammio, I didn’t think once about taking a photo of the idyllic scene. Instead, I paused, breathed deep, and absorbed it without the buffer of a screen in the way. Well played Finland.

Travel essentials

Getting there

Finnair flies from London Heathrow, Manchester and Edinburgh to Helsinki all year round, from £166 return.

Staying there

Santa Glass Villa at the Santalahti Resort cost from €550 per night based on two people sharing, including breakfast and activities.

Rooms at Kaunissaaren Hotelli Maja from €149, based on two people sharing.

More information

For more information on guided adventure nature walks around Ulko-Tammio and other areas of south-eastern Finland with Simo Peri, visit retkipiste.com

Ellie Seymour was a guest of Visit Finland and Visit Kotka-Hamina.

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