Aspendos Theater is an ancient Roman theater located in the city of Serik, Antalya province, Turkey. It is one of the best-preserved ancient theaters in the world and is considered to be an architectural masterpiece. The theater was built in the 2nd century AD by the Greek architect Zenon during the rule of the Roman Emperor Marcus Aurelius.

The theater has a seating capacity of approximately 15,000 spectators, and its unique acoustic properties have made it a popular venue for classical music concerts and other cultural events. The theater is famous for its impressive stage building, which is still intact today. It includes three floors of arcaded galleries with a colonnaded facade, adorned with sculptures and reliefs.

The theater was built with local limestone and is divided into three sections: the stage building, the orchestra, and the auditorium. The auditorium has a semicircular shape, and the seating area is divided into three levels, each with its own entrances and exits. The theater's acoustics were designed to ensure that even the softest sounds from the stage could be heard by the audience in the farthest rows.

Aspendos Theater has been used for various purposes throughout its history, including gladiator fights, festivals, and religious ceremonies. Today, it is a popular tourist attraction and is still used for concerts and performances during the annual Aspendos International Opera and Ballet Festival.