Aquincum
Budapest District III, Hungary
Aquincum ([aˈkᶣɪŋkũː], [ˈɒkviŋkum]) was an ancient city, situated on the northeastern borders of the province of Pannonia within the Roman Empire. The ruins of the city can be found in the Óbuda district of Budapest, the capital city of Hungary. It is believed that Marcus Aurelius wrote at least part of his book Meditations at Aquincum.
Monument data from Wikidata (CC0). Summary from Wikipedia (CC BY-SA).