3rd century in architecture
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Buildings and structures
=Buildings=
File:Rfmara - panoramio.jpg in Thessaloniki]]
- 209 – Ghal'eh Dokhtar castle built in Persia by future Sassanid Emperor Ardashir I.
- 216 – Baths of Caracalla, Rome, completed.{{cite web|title=Baths of Caracalla|url=https://www.britannica.com/topic/Baths-of-Caracalla|website=Encyclopedia Britannica|access-date=9 October 2017|language=en}}
- 224 – Palace of Ardashir built near Ghal'eh Dokhtar by Ardashir I.
- 266 – Bishapur city founded by Emperor Shapur I as a capital for the Sassanid Empire
- 290s – Diocletian's Palace, Split, completed.
- 298–299 – Arch of Galerius in Thessaloniki (Macedonia) built.