Quinta da Regaleira in Sintra, Portugal (© benitojuncal/Getty Images)

【October 24 2013】Carvalho Monteiro used the fortune he made in his native Brazil to build Quinta da Regaleira in Sintra, Portugal, in the early 20th century. Monteiro's interest in secret societies, alchemy, and esoteric philosophy influenced the structure's ornate façade and interiors, while the design of the castle itself – with tunnels, grottos, and this massive, walkable well – seems pulled straight from a tale of gothic romance.Explore breathtaking Gallery from the HuluTrip homepage over the past 5 years..