The Viridarium Cesi or “Viridario Magno” is a vast green space, partly fenced and terraced, located just outside the medieval walls, near the Porta Vecchia or Porta Ternana.
The area, which can be accessed through the remains of an arched portal, presents a small building on three floors which is probably of the sixteenth century.
The façade shows, on the ground floor, three arches, two of which are padded, which testify to the existence of an original small porch.
On the façade, at the peak of the second floor, there is a frame with four drips with lion-like protomes, which recall those on the facade of the ducal palace.
Similar drips, placed at the same height, but without protomes, partially covered by vegetation, are present on other sides of the building.
In the short stretch of wall leaning against the lower half of the right side of the building, almost aligned with the façade, opens up a niche rich in tartars that could have hosted a fountain with an exhibition of water.
Precisely in this area, as witnessed by the doctor and naturalist Giovan Battista Winther, many tree species were planted by Federico Cesi, including specimens of Taxus baccata L, whose samples of small branches with leaves, flowers and fruits used for his Syntaxis Plantaria and Chamaerops humilis L. (dwarf palm), a species with hermaphrodite and unisexual flowers, which gave him the samples depicted in the Plantae et Flores ms table. 976 c. 171
Source: I ” Travagliatissimi negotii” e le “filosifiche fatighe” di Federico Cesi il linceo nel “combattuto ritiramento” di Acquasparta: Il Viridarum cesiano, Gilberto De Angelis