Is Tröllafoss worth the Mosfellsdalur detour?

Yes, when you want a compact local waterfall hike near Reykjavík and already have space for Mosfellsdalur. It is less convincing as a main waterfall choice for a first Iceland trip.

Tröllafoss is a small gorge waterfall on Leirvogsá, tucked into the Mosfellsdalur countryside east of Reykjavík. Its appeal is not scale. The useful reason to go is the contrast: a rougher, greener, more local waterfall stop within reach of the capital.

Choose it when a Reykjavík base day needs fresh air, a short walk, and a place that feels removed from the city without becoming a full route commitment. Leave it out when your plan still needs Gullfoss, Skógafoss, Þingvellir, or another stronger first-trip anchor.

Photo guide

Tröllafoss Waterfall in photos

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The river approach is part of the visit, so weather and footing matter more than the drive distance suggests.

Worth the stop?

When this stop makes sense

Good match for

  • Reykjavík-based self-drivers wanting a quieter waterfall
  • travelers comfortable with a rougher short walk
  • Mosfellsdalur days with room for one nature stop
  • photographers who like small gorge waterfalls

Think twice if

  • first-time visitors choosing one headline waterfall
  • travelers needing polished paths and clear facilities

Pair it with

ReykjavikMosfellsdalurHelgufossGljúfrasteinn

What the Leirvogsá gorge visit feels like

The visit is about finding water, rock, and a narrow river setting rather than arriving at a polished viewpoint.

Tröllafoss is strongest as a close gorge waterfall, not as a broad roadside spectacle.

The waterfall sits in a rocky fold of the Leirvogsá river. Sources describe a small gorge, rough surrounding terrain, and a waterfall that is easy to miss if you expect obvious roadside infrastructure.

That roughness is also the charm. The dark rock, river sound, green slopes, and tight watercourse make the stop feel more personal than many built-up attractions. The tradeoff is that the approach asks more judgment than a signed pull-off.

How much effort the hidden waterfall asks

Plan for a short outing with uneven ground, a gravel approach, and a route that can feel informal near the river.

The waterfall rewards close looking, but the rock and river setting make footing part of the decision.

Several source pages point to limited signage, gravel-road access, and a walking approach from the Skeggjastaðir side or along the river. Keep the time range flexible because the exact feel depends on vehicle comfort, weather, and how clearly your group follows the path.

  • Go when a rougher short walk sounds like part of the reward.
  • Skip it when wet rock, mud, or vague route-finding would frustrate the group.
  • Keep children and less confident walkers away from slippery river edges.
The river approach is part of the visit, so weather and footing matter more than the drive distance suggests.

Where Tröllafoss fits beside Helgufoss and Gljúfrasteinn

The waterfall works best inside a small Mosfellsdalur cluster, especially when you want nature plus one cultural or valley stop.

The easiest way to make Tröllafoss useful is to keep it near other capital-area stops. Helgufoss gives you another small waterfall comparison, Gljúfrasteinn adds Halldór Laxness context, and Mosfellsdalur itself gives the day a quieter countryside frame.

It can also sit on a loose drive toward Þingvellir, but it should not compete with the main Golden Circle sequence. If the day is already built around Þingvellir, Geysir, and Gullfoss, Tröllafoss usually belongs only if you have spare time and good conditions.

The surrounding Mosfellsdalur landscape is why Tröllafoss works better as a cluster stop than as a famous-name detour.

What to check before relying on this local stop

The waterfall is close to Reykjavík, but the practical checks are the same ones that matter for any rougher Iceland walk.

Before committing, check official weather, road, and safety information. Rain, ice, strong wind, and poor visibility can make a short informal path feel much less worthwhile, especially near slippery rock and moving water.

Useful checks

  • Use for Iceland travel alerts and outdoor safety guidance.

  • Use before relying on gravel-road access or winter approaches.

  • Use for wind, rain, visibility, and warning checks.

Is Tröllafoss the same as Tröllafossar near Borgarnes?

No. This page covers Tröllafoss in Mosfellsdalur near Reykjavík on Leirvogsá, not the West Iceland waterfall near Borgarnes.

Is Tröllafoss worth visiting without a car?

Usually not. The practical value is strongest for self-drivers who can handle the approach flexibly and change plans if conditions are poor.