Below is the first sentence of the last paragraph on page 222.
Pluribus levioribus proeliis factis, tandem copiae adversae ad Pharsalum in Thessalia sitam castra posuerunt.
Could anyone please tell me which noun sitam agrees with?
Sitam: accusative singular feminine
Castra: plural
Thessalia: ablative
Pharsalum: masculine
Copiae: nominative plural
So sitam does not seem to belong to any of them.