Urridafoss

Urridafoss carries more water than any other waterfall in Iceland - the Thjorsa is the country's longest river and drains a very large glacial catchment - though the drop is only about six metres, so it reads as a wide powerful rapid rather than a spectacle of height, which is why far fewer people stop here than at falls a fraction its volume. The rock beneath is part of the Thjorsahraun, thought to be the largest lava flow from a single eruption in the world since the last ice age. The fall has been proposed repeatedly as a hydroelectric site; the plans have been contested for years and the outcome is not settled, which is worth knowing when visiting.

What you actually see

• Iceland's greatest volume - the most water of any fall in the country.
• Only six metres of drop - power rather than height.
• The Thjorsahraun beneath - among the largest single lava flows since the ice age.
• A contested hydro site - damming proposed repeatedly and still unresolved.

When to go

May to September. An hour.

Honest expectations

Visitors expecting a tall waterfall are disappointed - the point is volume. Facilities are a small car park and a path. Banks are slippery and unfenced in places. It is close to route 1 and easy to combine with other stops.

Nearby

Selfoss is west along route 1; Hekla stands north.