Right on the old harbour, you'll find Harpa, our dazzling concert hall that's a must-see even if you're not catching a show. Its famous glass honeycomb exterior, inspired by Iceland's basalt columns, plays with the light all day, reflecting the sea and sky. Feel free to wander inside and explore the main floors; the scale of the architecture is just as impressive from within, and the views over the water to Mount Esja are fantastic.