Signore Buchelli's Secret In my room (21) of the hotel at Rennes-Le-Château there's a weird drawing (look at the
linked image).
That drawing is a small part of a large drawing with ground plans and religious buildings, from The Iconographic Encyclopedia of Science Literature and Art, 1851 (look at the
linked image).
The circle and the square are related to the buildings around them (look at the
linked image).
The circle is the ground plan of The Tempietto of San Pietro in Montorio (Rome) -
Wikipedia:
The so-called Tempietto (Italian: "small temple") is a small commemorative tomb (martyrium) built by Donato Bramante, possibly as early as 1502, in the courtyard of San Pietro in Montorio. The Tempietto is considered a masterpiece of High Renaissance Italian architecture.
The square is the ground plan of the Basilica of Santa Maria Assunta (Genoa) -
Wikipedia:
Santa Maria Assunta is a Renaissance church in Genoa, Italy. It is located on a residential sector called Carignano located on the hills just above city center, thus the church is also known as Santa Maria Assunta di Carignano.
In
this folder there are photos of the 2 buildings.