Here is a real pearl of Italian 16th-century architecture: Palazzo Farnese in Caprarola, Viterbo. It is a mannerist wonder, an aristocratic retreat, a delightful villa and a fortified residence, designed by Jacopo Barozzi da Vignola (who transformed an early project by Antonio da Sangallo the Younger) and built between 1559 and 1575.
Alessandro Farnese the Younger – created a cardinal at the young age of 14, by his grandfather, pope Paul III – entrusted Vignola with reviewing Sangallo's designs, although he maintained the formidable pentagonal structure that gives the building a peculiar grandiosity, with a harmonious mix of military and civilian architecture lines.
Fonte: Italian Ways