Ancient theatre of Lyon, Roman theatre in the 5th arrondissement of Lyon, France

The ancient theatre of Lyon is a single Roman theatre built against the slope of Fourvière hill, with concentric rows of stone seating curving around a flat orchestra floor. Its cavea was built in stages: an initial theatre of about 5,700 seats, later enlarged with a third tier of seating to a diameter of 108 m and a capacity of 10,000. Behind the seating stand ruined vaulted walls and staircases; the neighbouring Odeon is a separate monument.

The theatre was built against the Fourvière hillside in two phases. A first structure with about 5,700 seats was erected in the early Empire, possibly under Augustus around 15 BC, though some scholars place it under Nero. A third tier of seating was added later, bringing capacity to an estimated 10,000. The dating of this enlargement under Trajan or Hadrian remains hypothetical.

The name Nuits de Fourvière now covers the summer festival held in the theatre, with performances staged on the orchestra floor beneath the tiers. Suetonius reports that Caligula organised Greek and Latin eloquence contests at Lugdunum, possibly here, since the Odeon did not yet exist. A fragment of Dio Cassius notes that a dance master expelled from Rome charmed the theatre's audience in the early 3rd century.

The theatre is reached on foot from the Vieux Lyon side by climbing the steep streets and stairways of Fourvière hill; the site lies on the Minimes terrace just below the summit. The tiers are uneven ancient stone, and the upper seating is bordered by a metal railing. The orchestra floor and the paved area beside the ruins are level ground.

The stage wall was quarried away in the 12th century for buildings such as Saint-Jean cathedral, and a lime kiln was installed in a staircase of the neighbouring Odeon. The hill's gravel and mud then buried the remains for centuries.