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Key takeaways<\/p>\n
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- Geologically young:<\/strong> Keri\u00f0 is roughly three millennia old by the most widely cited estimate, though some tour listings quote older figures \u2014 the honest answer is “about 3,000 years, possibly more”.<\/li>\n
- The numbers:<\/strong> about 55 metres deep from rim to water and roughly 170\u2013270 metres wide \u2014 small enough to walk the full rim in half an hour, big enough to feel like a proper crater.<\/li>\n
- The lake has no river inflow:<\/strong> it is fed by groundwater, so its surface level quietly tracks the water table rather than any stream.<\/li>\n
- Access is simple:<\/strong> a small entry fee paid at a self-service kiosk, parking by the crater, and a rim path that loops in around 30\u201340 minutes.<\/li>\n
- Golden Circle country:<\/strong> it sits near Selfoss and Gr\u00edmsnes, an easy add-on to \u00deingvellir, Geysir and Gullfoss \u2014 and it is one of the few such stops you can experience in under an hour.<\/li>\n<\/ul>\n<\/div>\n
\nQuick answer:<\/strong> treat Keri\u00f0 as a 30\u201360 minute stop. Pay the small fee at the kiosk, walk the complete rim loop, look down at the lake, and go either early or late in the day \u2014 the red slopes photograph best in warm side light, and the tour-bus crowds cluster around midday. Pair it with a Golden Circle run and you have a full, varied day without much driving.<\/p>\n<\/div>\n
\n~3,000 yrs<\/strong>the widely cited age of the crater; some estimates run older<\/span><\/div>\n55 m<\/strong>depth from the rim to the surface of the crater lake<\/span><\/div>\n170\u2013270 m<\/strong>width across the crater \u2014 a rim loop of roughly 30\u201340 minutes<\/span><\/div>\nSmall fee<\/strong>self-service kiosk entry; no ticket office, no booking needed<\/span><\/div>\n<\/div>\n - The numbers:<\/strong> about 55 metres deep from rim to water and roughly 170\u2013270 metres wide \u2014 small enough to walk the full rim in half an hour, big enough to feel like a proper crater.<\/li>\n