An Odeon, also called Odeion, was an ancient building used for musical performances, competitions and council meetings. Mostly it had a semicircular ground plan and differed from the theatre in that it was roofed over like a bouleuterion. The building, which was mostly built on a rectangular ground plan, often had the form of a small theatre hall with rising rows of seats around a central or front lecture area. The rising rows of seats could be semi-circular (Miletus) or rectangular (Priene). However, there were also simple solutions in which rows of benches or chairs at ground level served as seating (Adada).
The transition from the Odeon to the Bouleuterion often seems to have been fluent. While in most pure Bouleuterion ("town hall") no archaeologically visible differentiation of the social groups can be discerned, they are often provable in pure ancient odeens. One exception seems to be the Bouleuterion of Patara, which served as the central assembly building of the Lycian League. The subdivision of the cavea into five kerkides and the seat of honour in the form of an exedra in the middle of the cavea indicates certain differences in rank.

Other Odeons / Bouleuterions in preparation

Adada

Administrative building called Bouleuterion with high-quality brickwork with Hellenistic features.

Bouleuterion or Odeon. Probably erected towards the end of the 1st century AD.
Capacity: unknown

Bouleuterion from Hellenistic times. The building has not yet been excavated.
Capacity: unknown

Odeon from the 2nd century A.D. One of the best preserved Odeons in Turkey.
Capacity: 900 spectators

Odeon or little theatre. Probably built around the 1st century AD.
Capacity: unknown

Odeon from the 2nd century A.D., is located directly at the lower Agora.
Capacity: approx. 500 spectators

Bouleuterion probably from the 1st century BC, located at the end of the upper agora.
Capacity: approx. 300 council members

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Bouleuterion from the reign of Emperor Hadrian (117-138 AD).
Capacity:500-600 Council members

Kaiser temporal bouleuterion at the Agora, integrated into the well preserved row of shops.
Capacity: unknown

Bouleuterion from the 2nd century BC, divided by a wall in Byzantine times.
Capacity: approx. 400 persons

Bouleuterion, built between 175 and 163 BC as a foundation of the Milesian brothers Timarchos and Herakleides.

Gerontikon/Bouleuterion from the 1st century BC, rebuilt in the 2nd century AD.
Capacity: 600-700 Council members

Sagalassos Bouleuterion

The Bouleuterion was conquered at the turn of the 2nd to the 1st century BC.
Capacity: until 1450 council members

Bouleuterion from the 2nd century B.C. The rows of seats were arranged at right angles.
Capacity: up to 500 council members

Bouleuterion from the 1st century A.D. From 200 A.D. the bule met in the newly erected Odeon.
Capacity: approx. 220 council members

Odeon, construction started under Augustus, was only finally completed after 200 years.
Capacity: approx. 1500 spectators

Stratonikeia

Troy

Odeon from Hellenistic times. Only small remains of the wall are preserved.
Capacity: unknown

Bouleuterion from the 1st century A.D. On the outer wall price list of the emperor Diocletian.
Capacity: approx. 200 council members

Odeon from the 2nd century A.D. Conversion at the instigation of Hadrian.
Capacity: approx. 1000 spectators

Other Odeons / Bouleuterions in preparation