
Katla Ice Cave & South Coast Tour from Reykjavík
12 hours · From Reykjavík
South Iceland
You see it from the Ring Road long before you reach the turn-off: a thin white ribbon dropping off an old sea cliff, with a line of tiny people in bright rain jackets filing behind it. That line is the whole point. At Seljalandsfoss you don't just look at the waterfall. You walk round the back of it.
Seljalandsfoss is the first big stop on almost every South Coast trip in Iceland. The water falls about 60 metres from the edge of the old coastline into a shallow pool, and a path loops behind the curtain through a hollow in the cliff. From inside, the light comes through the water and everything, including you, gets wet.
The loop behind the falls takes ten or fifteen minutes if you don't stop, which nobody does. The path is rocky, uneven and permanently soaked by spray, so wear shoes with real grip and a waterproof jacket. Camera lenses fog and drip. Phones in a pocket survive; phones held up at arm's length for a slow-motion video sometimes don't.
Then keep walking. A few hundred metres north along the cliff is Gljúfrabúi, a second waterfall tucked almost completely inside a narrow gorge. You step on stones up a stream into the crack in the rock, and suddenly you're standing in a mossy chamber with the water thundering down in front of you. Fewer people bother. More people should. Your feet will get wet here too.
There are a few smaller falls along the cliff between the two, and on a clear day the view back across the flat farmland towards the Westman Islands is worth turning round for.
Late afternoon and summer evenings give the best light. Stand behind the curtain and you're looking out west into the low sun, with the spray glowing gold. Around midsummer, when it barely gets dark, you can come late at night and have it almost to yourself. Midday brings the tour buses.
Winter is a different place. The path behind the waterfall freezes, the spray coats the rocks in ice, and the loop is often closed off for safety. You can still see the falls from the front, and icicles hanging off the cliff are a decent consolation prize. If the path is roped off, stay out. Every winter somebody climbs over, and ice under a waterfall is exactly as slippery as it sounds.
Pro tip: see Gljúfrabúi first, while you're still dry enough to care, then walk behind Seljalandsfoss on the way back to the car. You'll be soaked either way, but only once, and only for the drive to the next stop.
Seljalandsfoss is roughly 130 km from Reykjavík, well under two hours' drive east on Route 1 past Hveragerði and Hvolsvöllur. The turn-off is signposted and you'll see the falls from the main road anyway. There is paid parking right at the falls, charged per car, paid at a machine or through the parking app. Plan on 45 minutes to an hour if you want to do both waterfalls properly without rushing.
It pairs naturally with the rest of the South Coast: Skógafoss is about half an hour further east, and Sólheimajökull glacier, Reynisfjara black sand beach and Vík are all within an hour or so beyond that.
Rather not drive? Nearly every South Coast day tour from Reykjavík stops at Seljalandsfoss, including small-group trips, tours combined with a glacier hike or the Katla ice cave, and longer days out to the Jökulsárlón glacier lagoon. Tours that include Seljalandsfoss are below.

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