Gluggafoss

Gluggafoss, also called Merkjarfoss, drops about forty-six metres in two stages on the Merkja river, and the reason for its name is the rock: the lower section runs through holes worn into soft palagonite, so the water disappears and reappears through openings that look like windows. Because the rock is soft, the shape is not fixed. Ash from Hekla's eruption in 1947 scoured the fall heavily and altered the windows, and the river has been reworking them since. A path runs up the side to a viewpoint level with the upper drop, and there is usually nobody else there despite it being fifteen minutes off the ring road.

What you actually see

• Water through windows - holes worn in soft palagonite on the lower drop.
• A shape that keeps changing - the rock erodes fast and the openings move.
• Scoured by Hekla in 1947 - ash from that eruption reworked the fall.
• A path to the upper level - a viewpoint beside the top drop.

When to go

May to September; reachable most of the year when road 250 is clear. An hour.

Honest expectations

The upper path is narrow, muddy and unfenced above the drop. In low water the windows are less dramatic than photographs suggest. There are no facilities. The road in is partly gravel.

Nearby

Seljalandsfoss is east; Hvolsvollur and the saga sites are south.