The Rio Grande in flood is a powerful, fast-moving, unpredictable river, and crossing it on foot or on horseback without a bridge required both physical capability and a specific knowledge of where and how to cross safely.

The wrong choice of crossing point could mean drowning; the right choice required knowledge that only experience or local guidance provided.

The Apache bands’ ability to cross rivers quickly and reliably — moving through the specific geographical obstacles that pursuing forces hoped would slow or contain them — was one of the tactical advantages that made the resistance sustainable.

A column of cavalry following a band could be delayed significantly at a river crossing if the ford was difficult or if the river was in flood.

The band that had crossed could gain enough time to establish an advantage before the pursuit resumed.