Where did they keep the mules in garrison?

[M. Demetrius]

If by "in garrison" you mean during the long winter non-battle season, that's one thing. For a campaign fort, in Polybius (in a book I no longer have) there was a mention of how a campaign fort was constructed, the order of building/pitching tents, digging the ditch/berm, and who was responsible for what. In that passage, it said that the ditch was placed outside of javelin distance from the tents, etc., and the horses were tethered in the grassy area between the berm and the fort.

Wish I could find that book again, and cite the specific passage. Maybe someone else could help out here?