The Teatro all'antica ("Theater in the style of the ancients") is a theatre in Sabbioneta, northern Italy; it was the first free-standing, purpose-built theater in the modern world. The Teatro all'antica is the second-oldest surviving indoor theater in the world (after the Teatro Olimpico in Vicenza), and is, along with that theater and the Teatro Farnese in Parma, one of only three Renaissance theaters still in existence.
The theater was constructed in 1588 and 1590 by the celebrated Vicentine architect Vincenzo Scamozzi under a commission from Duke Vespasiano I Gonzaga, as part of Gonzaga's effort to turn his tiny Ducal seat into an idealized classical city. The importance that theater had come to hold, as a sign of the civilized society that the Duke was trying to create, is indicated by the prestigious location that was reserved for the theater in the principal street of the town, the Via Giulia, and by the fact that a separate building was erected to hold the theater. This prestige location had a cost, however, in the form of a cramped and narrow setting that could be successfully converted into a theater only by the considerable ingenuity of one of the Renaissance's most gifted architects.
The influence of the Teatro Olimpico upon the Teatro all'antica is evident in a number of features—most notably in the colonnade at the rear of the seating area and in the set designs. Such influences are to be expected; Scamozzi had overseen the construction of the Teatro Olimpico following the death of the great Andrea Palladio, who had laid out its original design. In particular, Scamozzi had been responsible for the remarkable perspectives which form the onstage scenery at the Teatro Olimpico.
However, the Teatro all'antica was a much different theater, in part because of the different building in which it was placed, and in part because Scamozzi had learned important lessons as a result of his labours at the earlier theater. The theater building is roughly three times as long as it is wide, whereas the space occupied by the Teatro Olimpico is approximately square. The longer, narrower structure of the theater building meant that Scamozzi was unable to build the seating area in the form of the semicircle that had been seen by Palladio as the ideal form for an audience, based on the model of ancient Roman theaters. Where the wide, shallow space available in the converted building that was used to house the Teatro Olimpico had forced Palladio to stretch the ideal semicircle into an ellipse, the opposite change was forced upon Scamozzi in Sabbioneta, and the seating area was transformed into a horseshoe.