Marstrand Island, Marstrandsön in Swedish, is a small island off the coast north of Gothenburg with a fortress on its summit, a town of wooden houses along its harbour and bare granite everywhere else. The island is car-free: you leave the car on the neighbouring island of Koön and cross on a passenger ferry that takes about two minutes. That short crossing is what makes the place work. Once ashore there is no traffic, the harbour front is a promenade, and every lane ends in either water or rock.
The town is tiny. The urban area counted 349 residents at the end of 2023, and on a summer weekend the visitors outnumber them many times over. Come for a day from Gothenburg, or stay a night if you want the island to yourself after the day-trippers have taken the last boats back. The Gothenburg page covers the city you will most likely start from.
What you will see
Carlsten Fortress fills the top of the island and is the reason most people make the trip. Marstrand became Swedish with the Peace of Roskilde in 1658, and a first stone fort went up in 1660. The fortress you walk through today is later and much larger: Erik Dahlberg’s expansion began in 1682, and the complex was only declared complete in 1860, by which point it had spent most of its working life as a prison. At its peak it held 232 prisoners; the best known was the thief Lasse-Maja, brought here in 1813. The last prisoners left in 1858. The tower carried a lighthouse from 1781 to 1868, and in the twentieth century the site housed a coastal radar station for about thirty years, until the National Property Board, Statens fastighetsverk, took the fortress over in the autumn of 1993. A guided tour is included in the admission; Swedish-language tours leave at 12, 14 and 15 in season, with a 16.00 tour added in high summer. The walls, the tower and the view across the archipelago are the reward for the climb.
Below the fortress the town keeps a medieval church from the 13th century, Marstrands kyrka, and a local heritage museum run by the Marstrand Hembygdsförening. Strandverket, the old shore battery, now hosts art exhibitions, concerts and events. Guided Lasse-Maja walks tell the island’s history through its most famous inmate; ask at the tourist office for the next departure.
The rest of the island is open ground. Walking paths run through rocky coastal terrain round the outside of the island, and a full circuit fits into an afternoon with time left to swim from the rocks. Kungälv municipality lists a public bathing spot on the island and an annual west-coast sea festival, Västerhavsveckan, among its events. Marstrand is also a sailing town: the Match Cup regatta is the fixture that fills the harbour with crews and spectators, and yachts crowd the guest berths all summer. The tourist office’s overview page gives no dates for the regatta, so check them before you plan a visit around it, and expect the town at its busiest that week.
Visiting
The island itself has no gate, no opening hours and no ticket; the facts box carries the official website. Carlsten Fortress has all three. For 2026 it opens at weekends from 3 April to 31 May, 11.00–15.00, with weekday visits by arrangement over the phone. In June it opens daily 11.00–17.00 and stays open over Midsummer, 19 and 20 June, without guided tours. High season runs from 1 July to 9 August, daily 10.30–18.00, then 11.00–17.00 through the rest of August, and in September the gates open at weekends only, 11.00–15.00.
Admission is 120 kr for adults and 60 kr for children aged 5 to 15; under-fives enter free with an adult, and leashed dogs are welcome at no charge. The Fortress Games, a costumed weekend with its own programme, take place on 25 and 26 July 2026 from 12 to 18 and cost 195 kr for adults and 95 kr for children. The fortress hotel, Soldathotellet, is open year-round, which is the way to see the place out of season; hotel bookings go through +46 303-602 65, and weekday fortress visits are arranged on +46 303-611 67.
Getting there
Marstrand lies about 50 km north of Gothenburg by the tourist office’s reckoning, which puts the journey at about 50 minutes by car, an hour by bus and an hour by car from Landvetter airport. The fortress’s own site makes it about 45 km; either way it is a half-day out, not a long haul.
By public transport the route changed in 2024. Since the timetable change on 17 June 2024, Västtrafik’s line 302 is a local bus within Kungälv municipality, running Marstrand–Ytterby–Kungälv, and it no longer continues to Gothenburg. Every trip calls at Ytterby station and connects with the train, so from Gothenburg you ride the train to Ytterby and change. The bus runs every 30 minutes in weekday rush hours and hourly in the evenings and at weekends. Kungälv sits in Västtrafik zone B, so a zone A ticket bought for Gothenburg will not cover the whole trip. The fortress website still describes a direct bus from Nils Ericson Terminal; that service ended with the change, so trust Västtrafik’s journey planner instead.
Driving, you park on Koön. Hamnplan is the car park closest to the ferry; Brandstationen and Käglan allow a maximum of 24 hours; Hareslättsvägen is the long-stay option, up to 14 days. Parking charges are not published on the page, so read the signs.
The ferry, Marstrandsfärjan, is run by Kungälv municipality, and Västtrafik sells no single tickets for it. You buy at the customer-service booth at Koön ferry berth, Lilla Varvsgatan 2 B. A ticket is a return, valid for 24 hours and one trip over and back; the youth fare covers ages 7 to 19, and tickets are neither exchanged nor refunded. You pay only on the way over: the crossing back from the island is free. Boats leave every 15 minutes through the day; at night some sailings are on request, and you press the button at the berth at least 5 minutes before departure. A summer timetable applies from June to September, with a separate winter one. Västtrafik period tickets, school cards and senior tickets for zone B are valid on the ferry; a Västtrafik single ticket is not. The operator does not publish the foot-passenger fare on a readable page, so check it at the booth.
From the ferry, turn right along the quay for about 200 metres, then left up Kungsgatan and follow it uphill to the fortress gate; the final stretch is steep, and there is no step-free alternative on the island’s roads.
Nearby
Koön, where you leave the car, is an island too, joined to the mainland by road and with its own marina and the ferry berth. Kungälv, the municipal seat, is where the bus meets the train and the natural place to break the journey. Gothenburg is the obvious base: its southern archipelago is the other car-free island trip from the city, reached on a tram ticket rather than a ferry fare, and the city page lists the rest of the day trips along this coast. For trains, buses and tickets across the country, see the Sweden transportation page, and for the country as a whole the Sweden page.