Can You Swim in the Oslofjord?
Where swimming actually happens
On the islands and along the shoreline, not in the shipping lane. Langøyene is the summer island, reached by Ruter’s line B2, which runs in summer only. The near islands on line B1 — Hovedøya, Lindøya, Gressholmen, Bleikøya and Nakholmen — go from Rådhusbrygge 4 on an ordinary Ruter ticket, the same quay two sightseeing cruises use. The islands.
The temperature, honestly
High teens at the very best of summer, a couple of degrees at the end of winter. Those figures come from a climate aggregator rather than a marine source, which is why this page will not give you a decimal. The practical version: there is a short stretch of the year when the water is pleasant, a longer stretch when it is bracing and people swim anyway, and a stretch when it is not a recreational proposition.
Is it clean enough
The fjord’s health problem is not primarily at the surface where people swim; it is in the deep basins behind the Drøbak sill, where water renews slowly and, in several basins, the oxygen falls low enough that all life dies. That is a serious ecological story and a different one from bathing water. Check local advice for the day you are there rather than a page written in advance. The state of the fjord.
If swimming is the plan, take the ferry rather than a cruise and give yourself the afternoon. A sightseeing boat is ninety minutes of looking at water you cannot get into — the ferry option.
Frequently asked questions
Can you swim in the Oslofjord?
Yes, in summer, from the islands and the shoreline. The water reaches the high teens at the peak of summer and a couple of degrees in late winter, though those are approximations rather than marine readings. Where people actually swim.
Can you swim from an Oslofjord cruise?
No. The cruises do not stop, and five of the six never put you ashore. Only the six-hour island trip lands, and it is a walking trip: not wheelchair accessible, with climbing on the islands, and under-15s accompanied. Island hopping.
How do I get to a swimming island?
Ruter’s B1 line from Rådhusbrygge 4 serves the near islands on an ordinary Ruter ticket, and line B2 reaches Langøyene in summer only. Ferry or cruise.