The most famous and iconic palace in Sintra is the Pena Palace (Palácio Nacional da Pena). Perched atop a hill in the Sintra Mountains, this 19th-century Romanticist masterpiece is renowned for its vibrant red and yellow facades and its eclectic mix of Neo-Gothic, Neo-Manueline, Neo-Islamic, and Neo-Renaissance architectural styles. Originally a medieval chapel and later a monastery, it was transformed into a royal summer residence by King Ferdinand II. Completed in 1854, the palace is surrounded by the vast Pena Park, featuring exotic plants and winding paths. As a UNESCO World Heritage site and one of the Seven Wonders of Portugal, it attracts millions of visitors annually who come to marvel at its fairy-tale appearance and the panoramic views it offers of the Portuguese Riviera and, on clear days, as far as Lisbon.