The Inverted Tower - Sintra, Portugal - New Images

An underground tunnel with a spiral staircase, supported by carved columns, down to the bottom of the well through nine landings. The nine hole round landings, separated by fifteen steps, evoke references to Dante's Divine Comedy, and may 

 represent the nine circles of hell, paradise, or purgatory.

The well is connected to laberíticas caves that lead to a spooky garden surrounded by a lake.

The land that is now Quinta da Regaleira had many owners through time. 

But in 1892 it belonged to the Barons of 

Regaleira, a family of rich merchants from Porto, when it was purchased that year by Carvalho Monteiro for 25,000 réis. Monteiro wished to build a bewildering place where he could gather symbols that would reflect his interests and ideologies. With the assistance of the Italian architect Luigi Manini, he designed the 4-hectare estate with its enigmatic buildings, believed to hide symbols related to alchemy, Masonry, the Knights Templar, and the Rosicrucians. The architecture of the estate evokes Roman, Gothic, Renaissance and Manueline architectural styles. The construction of the current estate commenced in 1904 and most of it was concluded by 1910.