Four days in Helsinki: An imperial capital that behaves like a small town

Start at the sea end of Esplanadi and walk inland. The park is a narrow strip of lawn and lime trees between two boulevards, running from the market square up towards the shops, and in summer it is where the city sits down: office workers on the grass, a free concert most evenings on the stage at the harbour end, and an ice cream in most hands. The gulls have worked out what the ice creams are for, so hold on to yours.

The Old Market Hall is the low red brick building on the quay, open since 1889 and still the best eating on the waterfront. It is a single aisle of stalls selling smoked fish, reindeer, cheese, soup and bread, with a handful of counters where you can sit and eat it. The famous find is a stall selling beaver sausage; the sensible order is a bowl of salmon soup. Outside on the cobbles, the open air market sells berries and produce all year, and in high summer the thing to buy is a bag of sweet green peas, which you pop out of the pod and eat raw as you walk.

Then climb Senate Square in the evening, when the tour groups have gone and the light is coming off the water. Engel's cathedral stands at the top of a very wide flight of steps, white, green domed, and with the twelve apostles standing along the roofline looking down at you. It was finished in 1852 and it is a better building from outside than in, which is convenient, because there is now a charge to go in and the interior is austere even by Lutheran standards. The three sides of the square below it, the university, the government palace and the merchant's house on the corner, were all designed to make a town of a few thousand people look like the seat of a grand duchy.

Uspenski Cathedral is ten minutes from the market square, up a rock on the Katajanokka side of the water, and you will have seen its red brick and its five gold domes from every harbour view already. It is the largest Orthodox church in western Europe and it serves a Finnish minority of about sixty thousand people, a leftover of the Russian century. The domes are finished in twenty two carat gold, the interior is dark and heavy with icons after the whitewashed restraint of the Lutheran cathedral, and it takes twenty minutes.

Then take the ferry. Suomenlinna is a fortress spread over six linked islands about twenty minutes out, and the boat leaves from the market square on an ordinary HSL ticket. Sweden began building it in the 1740s at ruinous expense to hold its eastern flank, called it the Gibraltar of the North, and then lost it in 1808 without much of a fight: the Russians besieged it, no relief came, and the commander Carl Olof Cronstedt surrendered after two months. Finland was ceded shortly afterwards. Cronstedt was condemned as a traitor by a king who was himself deposed soon after, and spent the rest of his life gardening.

What makes it worth a day rather than an hour is that it is a real place. Eight hundred people live on the islands year round, there is a school and a shop, and the ramparts, dry dock, tunnels and grass banks are simply the landscape they live in. Walk the blue signposted route across the bridges to the King's Gate at the far end, then come back along the southern shore where the cannons face out to sea and people swim off the rocks in July. The Ehrensvärd Museum, in the commandant's house on the main courtyard, is the one indoor stop that explains the rest: it belonged to Augustin Ehrensvärd, who built the fortress and is buried in the courtyard outside, and it holds his furniture, weapons and ship models.

Temppeliaukio was quarried straight down into a granite outcrop in a residential block of Töölö and finished in 1969. From street level you see almost nothing, a low copper dome sitting in the rock like something that has landed badly. Inside, the walls are the blasted rock face, left rough and wet looking, and the dome above is twenty two kilometres of copper strip wound in a spiral. It is one room, it takes fifteen minutes, and the acoustics are so good that the concert schedule is worth checking before you go: hearing it used is a completely different experience from filing through it. Get there when it opens, because the coach parties arrive mid morning and it is not a big space.

Walk north west through Töölö to Sibelius Park, about twenty five minutes through quiet apartment streets, or take tram 2 most of the way. Eila Hiltunen's monument to Jean Sibelius, unveiled in 1967, is six hundred hollow steel pipes welded into a wave and weighing over twenty tonnes. When it was new, the argument about whether abstract sculpture was an acceptable way to honour a national composer was fierce enough that Hiltunen added a separate bronze face of Sibelius beside it, which is now the part everyone photographs and the part that has aged worst.

Café Regatta is two minutes further, a tiny red wooden hut on the shore that looks like somebody's boathouse and is packed from opening to closing. Coffee refills cost minus five cents, which is to say they hand you money back, and you sit outside on the rocks by the water whatever the weather.

Finish at the Yrjönkatu swimming hall, back in the centre. It is an art deco bath house from between the wars with a pool under a barrel vault and three saunas, and it operates on single sex days, men on Tuesday, Thursday and Saturday, women on Monday, Wednesday, Friday and Sunday. Swimming costumes are permitted and almost nobody wears one. The upper floor, afternoons only, adds a steam room, a wood heated sauna and a café where people sit in towels and drink beer between sessions. It is not a spa and it is not a tourist attraction. It is a public bath, and behaving like it is one is the whole etiquette.

Oodi is a public library, and Helsinki built it in 2018 as a civic statement costing close to a hundred million euros facing the parliament building across the road, which is roughly the point. The ground floor is a café and a hall, the middle floor has sewing machines, 3D printers, recording studios and kitchens that anyone can book, and the top floor is a single white curve of reading room under a wooden hull, opening onto a terrace with the whole government quarter laid out in front of it. It opens early, it costs nothing, and it is three hundred metres from the platforms.

The Ateneum, on the other side of the station, is the national gallery and the place to see what Finnish artists did with a national identity that was still being invented. The strength of it is the late nineteenth century room: Gallen-Kallela's scenes from the Kalevala, Schjerfbeck's self portraits thinning out towards the end of her life, Edelfelt painting Paris and Porvoo with the same brush. There is also a small international collection with a Van Gogh in it. Two hours covers it comfortably, one hour covers the Finnish rooms, and the cloakroom will take your luggage.