Palacio de Cristal (Crystal Palace), Madrid (must see)

Right by a quiet, man-made lake and surrounded by the towering chestnut trees of Retiro Park, you’ll find the Crystal Palace—one of Madrid’s most remarkable examples of iron-and-glass architecture. Initially built in 1887 as a giant greenhouse for the Philippine Islands Flora Exhibition, it was closely modeled on London’s famous Crystal Palace in Hyde Park.

With its wide glass panels and slender iron columns, the building feels light, almost dreamlike. Sunlight floods in from every angle, bouncing off the glass and casting reflections that shift throughout the day. Cast iron columns support the structure, creating a grand and elegant interior. A full restoration in 1975 helped bring it back to its former glory.

These days, the Crystal Palace isn’t home to tropical plants—but to art, regularly hosting temporary exhibits and installations that make creative use of the open, light-filled space. Admission is free, so you’re welcome to step inside and take it all in—whether you're there for the art or simply to soak in the atmosphere. And if you catch it at sunset, when the lights come on, the whole place seems to take on another life again.

Tip: If you’re after that perfect photo, aim for sunrise. The early light reflecting off the lake and catching the glass panels gives the whole place a magical glow.