[1] Its original location was about 10 km southwest of Eskişehir, at a place now known as Karaca Hisar; about the end of the fourth century B.C.

The Roman army that was based in Asia minor was spread thin, and the navy had moved west from the Northern city of Sinope, therefore the provincials were left exposed.

When the city was under threat, the people used dedicatory statues to build their wall quicker, indicating their rush to protect themselves against the invaders.

Byzantine emperor Manuel I Comnenus fortified Dorylaeum in 1175.The contemporary Byzantine historian Niketas Choniates relates that Manuel did not destroy the fortifications of Dorylaeum, as he had agreed to do as part of the treaty he negotiated with the Seljuk Turkish sultan Kilij Arslan II immediately after the Battle of Myriokephalon.

The sultan's response to this development was not a direct attack on Dorylaeum but the dispatch of a large army to ravage the rich Meander valley to the south.

[6] Dorylaeum was described by the Muslim author al-Harawi (died 1215) as a place of medicinal hot springs on the frontier at the end of Christian territory.