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Given free rein to design a palace in Portugal in 1904, a cashed-up, eccentric entomologist named Carvalho Monteiro came up with Quinta da Regaleira: a mishmash of architectural styles sprinkled with inscrutable symbols said to allude to secret societies.

The five-floor hilltop mansion, located in the southern coastal town of Sintra, mixes Roman, Gothic, Renaissance, and Manueline styles. Its surrounding gardens are a fantasy land of grottoes, fountains, statues, ponds, underground tunnels, and a deep, moss-covered Initiation Well, believed to be the former site of Masonic rituals.

Quinta da Regaleira’s architecture hides shapes and symbols relating to alchemy, Masonry, the Knights Templar, and the Rosicrucians. A Roman Catholic chapel in front of the palace depicts Catholic saints, with a few pentagrams thrown in for kicks. It’s a confusing mix, but one that’s undeniably beautiful.

Visit Atlas Obscura for more on Quinta da Regaleira.

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