Dettifoss is the most powerful waterfall in Europe and it's just an incredible sight to stand in front of the waterfall. You can get really close if you stay on the grass on the west side. However, the east side is also a very great option to get up close. There you will stand on the rocks very close to the edge so be careful and proceed at your own risk. We parked on the westside which is located here: https://maps.app.goo.gl/B6D3hinK6iKKzEGb9 it takes about 30 min in total to see Dettifoss and Selfoss.
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