Yes, the water and sky were really that blue. And yes, Opatija should be added to your travel bucket list ASAP! This little seaside resort town in the northern Croatian region of Istria is as charming and authentic as it gets. A favorite vacation destination of the Austrian royal family, Opatija is an influence of Austro-Hungarian, Italian, and Croatian cultures, architecture, and food. I visited here a few years ago with my family but couldn’t wait to come back!