Greeting to the Sun in Grad Zadar

You're standing on Zadar's waterfront, at the western tip of the peninsula, right where the harbour begins. Look down at your feet. That big glass circle set into the stone quay is the Monument to the Sun, in Croatian Pozdrav suncu, the Greeting to the Sun. It's twenty-two metres across and made of three hundred multi-layered glass plates. They sit flush with the paving, so you can walk straight across.