Seljavallalaug Pool is an iconic hidden gem tucked away in the mountains of South Iceland that will make you feel like you've stepped back in time. Built in 1923, it's the oldest swimming pool in the country and boasts stunning views. To get to the pool, you must take a flat 20 minute hike through a river bed. The changing rooms are co-ed and incredibly messy due to tourists not cleaning up after themselves; it's important to leave no trace when visiting. The water is filled with algae and the temperature is warm at best. Although there is no fee to swim here, bringing a plastic bag for trash and checking that all your belongings stay dry is important. It’s perfect for both swimmers and photographers looking for a unique experience on their Icelandic adventure.