Villa Adriana (Hadrian's Villa)
"The Italian Versailles. Fifteen miles outside Rome, near Tivoli, the creator of the Pantheon, Hadrian, built a 500-acre compound that rivals any royal residence in luxury and inventiveness. Scattered over seven miles were gardens, pavilions, palaces, theaters, temples, and baths of unprecedented fantasy. ...
An architect, poet, painter, and mathematician as well as a brilliant statesman, Hadrian reigned from 117 to 138 C.E. [AD]. Presiding over the zenith of Rome's wealth and geographic span, he personally inspected much of the Empire. His traveling entourage included surveyors, architects, decorators, and construction crews. He scattered Roman monuments throughout the Empire, leaving a legacy of mini Romes wherever he set up camp.
When the emperor built his dream retreat , he incorporated much of what he had seen during his travels. ...
Besides libraries, dining halls, and barracks, Hadrian built his own private island surrounded by a circular moat. A tiny villa on the isle offered seclusion where he could study his beloved Greek texts or entertain visiting philosophers."
from The Annotated Arch - A Crash Course in the History of Architecture, by Carol Strickland, Andrews McMeel Publishing, Kansas City, MO, 2001, page 21.