Even though magnificent royal residences in the Romantic style are often to be found in 19th and 20th century Europe, Sintra is a pioneer work of European romanticism, bringing together its incredible botanical richness and a diversity of monuments and buildings from a long period of history.

Sintra is world-famous as a "fairytale" landscape that serves as the ultimate example of European Romantic architecture. Designated as a UNESCO World Heritage site in 1995, it was for centuries the preferred summer retreat for Portuguese royalty and nobility, who were drawn to its cool mountain microclimate and lush, misty forests. The town is home to a dense collection of eccentric palaces, including the vibrant, "Crayola-colored" Pena Palace, which sits atop a high peak and blends Neo-Gothic, Neo-Manueline, and Islamic styles. Another major draw is the Quinta da Regaleira, famous for its "Initiation Wells"—mysterious underground spiral towers used for secret ceremonies. Sintra’s fame also stems from its influence on 19th-century landscape architecture; its gardens were the first in Europe to successfully integrate exotic flora from all over the world with local stone structures. The poet Lord Byron famously called it a "glorious Eden," and its combination of haunting Moorish ruins, opulent estates, and rugged Atlantic coastline makes it one of the most visited and photographed cultural landscapes in all of Europe.