From the quay at Aker Brygge you can see them: low green humps in the fjord, a scatter of small cabins, a sailing boat or two tacking between them. Those are the inner Oslofjord islands, and reaching them costs no more than a tram ride across town.
The Oslo ferries to islands such as Hovedøya, Lindøya, Gressholmen and Langøyene are part of the ordinary public transport network run by Ruter. A regular ticket or an Oslo Pass gets you aboard, and the closest island is about eight minutes away.
Each island has its own character, from medieval ruins and old gunpowder stores to cabin colonies, a former seaplane base and a sandy beach where you may pitch a tent. Here is how the boats work, and what you find when you step off.
Where the island boats leave from
The island ferries depart from the waterfront at Aker Brygge, just west of Oslo City Hall. VisitOSLO lists the stop as Rådhusbrygge 4, a short walk from Nationaltheatret station and the trams along the harbour.
This is not the same boat as the seasonal service to Bygdøy, which is covered by the Oslo Pass but not by regular Ruter tickets. If you are planning a museum day on that side of the harbour, our guide to the Bygdøy peninsula and its ferry crossings covers that route.
Because the ferry from Oslo to the islands belongs to the city network, there is nothing to reserve. Buy a ticket in the Ruter app before you board, and the same system that runs the trams and metro carries you across the water. Our piece on how Oslo's ferries, trams and subway interlock explains why that works so smoothly.
Line B1: a loop through the inner fjord
Line B1 is the year-round workhorse. It sails from Aker Brygge to Hovedøya, then on to Lindøya øst, Gressholmen, Bleikøya, Nakholmen and Lindøya vest, before calling at Hovedøya again on the way home.
The full circuit takes roughly an hour. You can ride it simply as an inexpensive fjord cruise, or step off at one island and catch a later boat on to the next.
Ruter's island boats are electric, each with room for around 350 passengers. On a still morning the quiet crossing feels closer to a drift than a commute.
In high summer the pattern shifts. From early July to the end of August, B1 skips Hovedøya and Gressholmen between 10:00 and 21:00, because so many people are queuing to come back. In that window an extra line, B1X, runs every 20 minutes straight to Hovedøya.
Hovedøya: monks, cannons and a protected island
The Oslo–Hovedøya ferry is the shortest crossing, and the island repays it. It is no more than about 800 metres across, yet its hill reaches 47 metres, the highest point among the inner fjord islands.
On 18 May 1147, Cistercian monks from Kirkstead Abbey in England founded a monastery here. It became one of the richest institutions in medieval Norway, until it was burned in 1532, after its abbot was drawn into the power struggle around the deposed king Christian II.
Much of the abbey's stone was later shipped across the water to expand Akershus Fortress, which still watches over the harbour you have just crossed. Even so, the surviving ruins are among the most complete of any medieval monastery in Norway.
Later centuries added a military layer. Two cannon batteries were built in 1808, during the Napoleonic Wars, and gunpowder magazines followed in 1826 on the island's high points. Several of these structures still stand beside the paths.
Hovedøya is a nature reserve, known for an unusually rich flora on its fertile, lime-rich soil. You may walk anywhere, but picking plants and taking rock samples is banned, which is stricter than the usual right to roam.
Most swimmers head for the two beaches on the west side. In summer a small café near the monastery ruins is open to visitors.
The cabin islands: Lindøya, Nakholmen and Bleikøya
Stay on B1 and you reach a different kind of island. Lindøya, Nakholmen and Bleikøya are dotted with small, brightly painted summer cabins, and their story is a working-class one.
In the early 1900s, families from Oslo's crowded east side began going out to camp on Lindøya in summer. Tents gave way to simple wooden huts, and in 1922–23 the state opened the three islands to regulated cabin building. Around 600 cabins were established.
Families with many children living in cramped back-courtyard flats were given priority for the plots. The cabins still stand on state land, and their low, modest shapes have changed little in a century.
Bleikøya has an older chapter as well. From 1885 to 1926 it housed a sanatorium for children with scrofula, a form of tuberculosis, before the cabins came there too.
The cabins themselves are private, so keep to the paths and the shoreline, which are open to everyone. The walk between the Lindøya øst and Lindøya vest piers makes an easy, pleasant hour between boats.
Gressholmen and Oslo's first airport
Gressholmen looks like a quiet green islet today, but from 1927 to 1939 it was Oslo's main airport. The aircraft were seaplanes, and the role ended when Fornebu opened on the mainland.
The old slipway with its rail tracks and the hangar are still there, now used for storing and maintaining boats. The island has grown together with its neighbours Rambergøya and Heggholmen, and much of the area is a nature reserve.
Both B1 and B2 call at Gressholmen, which makes it a handy stop if you want to switch from one line to the other.
The Langøyene ferry and the beach island
The Langøyene ferry is line B2, which runs from Aker Brygge via Hovedøya and Gressholmen. The trip out takes around half an hour, and Langøyene is the farthest of the regular island stops.
The name means "the long islands". There were once two, Nordre and Søndre Langøy, but the strait between them was filled in with waste deposits. The grassy plain in the middle is the surface of that old fill.
The city of Kristiania bought the islands in 1902, and although Langøyene lies within Nesodden municipality, Oslo still owns and manages it. A renovation from 2020 to 2022 brought a new beach, new toilets and clean drinking water.
Langøyene is the only island close to Oslo where camping is allowed. You may stay up to two days in the marked tent zones on the northern part, then you must leave for 24 hours before coming back for another stay.
Open fires are banned all year, though grilling is permitted at signed spots. The long sandy beach suits families, and the southern tip has a designated naturist area.
Seasons, timetables and the last boat home
The island ferries change timetable several times a year. B2 to Langøyene runs from spring into autumn; in 2026 its autumn timetable ends on 18 October, and from 19 October Ruter lists only B1 for the winter season.
B1 keeps sailing all year, so Hovedøya can be reached even in midwinter. Departures are fewer and daylight is short in the cold months, so check the Ruter app or the timetable PDF before you set out.
Pay close attention to the last departure. There is no water taxi service in Oslo, and VisitOSLO is blunt that the sea rescue service is not a ferry. In the rare cases where it does bring stranded visitors back, the fee starts at 5,000 kroner.
On hot summer days the last boat can fill up. Ruter says it will keep sailing until everyone has been taken back, but only if you are at the pier by the scheduled departure time.
Planning a simple island day
For a first visit, two islands are plenty. Take a morning ferry to Hovedøya for the ruins and a swim, then ride B1 onward to Lindøya or Gressholmen and come back in the late afternoon.
If you plan to hop between several islands, a 24-hour ticket is usually simpler than buying singles, since a single ticket is only valid for a limited time. The Oslo Pass covers the island boats as well.
Bring food and water, especially outside high summer. Hovedøya's café and the kiosk on Langøyene keep seasonal hours, and there are few other places on the islands to buy anything.
Pack an extra layer even on warm days. The wind on the open deck is cooler than in the streets, and the ride back, with the fortress walls and the city waterfront growing ahead of you, is often the best part of the day.
About Sofia Berg
Sofia Berg is a lifelong Oslo resident and travel writer with a passion for uncovering the city's hidden gems. She has been exploring and writing about Oslo for over ten years.