Seljalandsfoss is a stunning waterfall located in Iceland's South Region, right by Route 1. Dropping 60 meters, it's part of the Seljalands River that originates from the Eyjafjallajökull volcano glacier. What makes this waterfall extra cool is that visitors can actually walk behind it into a small cave for a unique experience. Just watch out for the mist! Oh, and fun fact: it was even featured in The Amazing Race and Justin Bieber's music video. So, if you're ever in Iceland, don't miss out on checking out Seljalandsfoss!