Credit: Courtesy of Aena

This city’s stunning architecture is on display from the moment you step into Ricardo Bofill’s new $1.7 billion T1 terminal at El Prat Airport ( Made of polished white granite and glass, the sword-shaped and eco-friendly structure—it’s outfitted with solar heating panels and electricity-saving glass walls—serves close to 100,000 passengers a day. Inside, you’ll find a full-service spa, six VIP lounges, a business center, and a 256,000-square-foot retail area with more than 70 boutiques, including Desigual and Ferrari. It’s all the more reason to show up the full two hours before your return flight.