Will I Get Seasick on the Oslofjord? A Guide for Nervous Passengers

Seasickness on the inner Oslofjord is rare. The water inside the Drøbak narrows is shut off from the open sea by an underwater sill and broken up by islands, so there is very little swell to feel. On a 3-hour private cruise from Tjuvholmen in light wind, hardly anyone reports nausea. The risk goes up with wind strength and on longer trips that cross the narrows into open water.

About one booking enquiry in ten asks about it. The question usually comes from somebody who got sick on a cruise-ship tender in the Caribbean or a whale-watching boat off Iceland and does not want a repeat. The inner Oslofjord is closer in feel to a large Scottish loch than to open sea: sheltered on three sides, pinched at the southern end, and walled off from the Skagerrak by a ridge on the seabed.

Motion sickness is individual, though, and worth planning around. The rest of this covers why the inner basin stays flat, what changes that, and what happens on board if you start to feel unwell.

Why the inner basin stays flat

The Drøbak Sill is a glacial ridge across the fjord at the narrows, 40 kilometres south of Oslo. Store norske leksikon puts the shallowest point of the channel at about 19 metres and describes the sill as the thing that limits water exchange with the inner Oslofjord. Everything north of it is effectively its own body of water, and swell coming up from the Skagerrak loses most of its energy on the way over.

Then there are the islands. Hovedøya, Bleikøya, Lindøya, Gressholmen, Nakholmen, Ormøya, Malmøya and Langøyene sit between the city and the open fjord as a wind-and-wave break. Even in a stiff westerly there is calm water behind one of them. We pick the route around where the wind is, not the other way round. The geology behind all of this is in what is the Oslofjord.

What changes the picture

Three things can put real motion under the boat.

Wind, particularly from the south. Above roughly 10 to 12 m/s the inner fjord chops up and a 28-foot boat starts to bounce once it leaves shelter. We move the route to stay leeward of the islands, or postpone.

Crossing the narrows. A Drøbak and Oscarsborg day trip takes you over the sill into water where ship traffic and ferry wakes produce a longer, slower swell. Gentle most days, but noticeable after the inner basin.

Going further than that. Past Filtvet or Hvasser, the outer Oslofjord behaves like sea. If you have a history of seasickness, say so before booking a trip that goes that far. Our standard 2-to-4-hour cruises stay inside the sill.

The other common trigger has nothing to do with the water. A heavy breakfast, or coffee and nicotine in quick succession, will make you queasy in flat calm. Eat something light an hour before.

If you know you are prone to it

Take medication an hour before boarding rather than after symptoms start, because tablets cannot catch up once you feel it. The standard over-the-counter option in Norway is Postafen (meclizine), sold without prescription at any Apotek; the patient leaflet on Felleskatalogen has the dosing. Cinnarizine, sold as Stugeron, works along similar lines. Both cause drowsiness in some people, so do not drive afterwards.

Acupressure wristbands help some people. The evidence for them is mixed, they are cheap, and they have no side effects. Ginger sweets or ginger ale take the edge off mild nausea, and there is a tin of ginger sweets on the boat.

On board the rules are short: stay outside in the air, look at the horizon, keep off your phone. Nausea comes from the mismatch between what your eyes report (a stable cabin) and what your inner ear reports (a moving boat). A fixed point on the horizon settles the argument.

If it happens anyway

Tell the captain straight away. What follows, in order:

1. The boat comes off the plane and slows, or stops.
2. You move to the centre of the deck, where there is least motion.
3. If that is not enough, we anchor in the lee of an island.

The inner fjord is full of sheltered bays, and from anywhere in the basin we can be at anchor in calm water inside five to ten minutes. Once the boat is still, recovery is quick. If you would rather go in, we go in, and there is no charge for cutting a cruise short.

Children

Toddlers are largely spared. School-age children are the group most likely to feel it, and it fades for most people in adulthood. For a child old enough to say something is wrong, the same rules work: light snack beforehand, air on deck, eyes up, no screens. Postafen is approved from six years old at half the adult dose, again per the Felleskatalogen leaflet. Our family boat tour article has more on cruising with kids.

Pregnancy

Pregnant guests cruise with us regularly. Ask a pharmacist or your midwife before taking anything at all, which puts the weight on the other tools: wristbands, ginger, a light meal, air on deck, and picking a calm day. The inner fjord on a flat morning is gentler than the taxi ride in from Gardermoen. Tell us when you book and we will move route and timing away from the choppy days.

What we will not do

We do not take the boat out in conditions past our weather criteria, whatever the guests want. Above about 12 m/s of sustained wind, or sustained swell over a metre at the narrows, we reschedule. Going anyway produces a bad cruise and a worse memory, and there is almost always a calm window the day before or the day after.

Seasickness is the easiest thing for a guest to worry about and the easiest one for me to fix. If somebody starts feeling rough, I anchor. Two minutes later we are sitting still in a sheltered bay with a glass of water. The colour comes back, and we either carry on or head in.

If you have a strong history of it

Tell us when you book. We pick the calmest day in your window, plan a route that stays inside the islands, and brief the boat. A 90-minute cruise instead of a 3-hour one is a reasonable first try. The route options are on our tours page, and the booking notes field is the place to raise it. Every message gets answered before we confirm.

Wind is the variable that matters here. Check the day's forecast on Yr. Medication details last reviewed against Felleskatalogen in July 2026.