KanjiJLPT N2
Stationed

stop-over, reside in, resident

Mnemonic

The lord's finest horse is stationed at the embassy gates. It never moves from its post—the lord commanded it to remain stationed there as a living symbol of power, standing guard through rain and sun, hooves rooted to the cobblestones like a parked chariot.
Additional thoughts
Visualize a grand horse frozen in place at iron gates, ordered by its lord to stay put. Link 'stationed' to both military posting and parking—the horse is essentially 'parked' by royal decree.
Quick recall
The lord's horse is stationed at the gates, frozen at its post by royal command.

Details

The keyword for 駐 is stationed. This kanji conveys the idea of being posted or placed at a particular location for a period of time, much like a soldier or official assigned to a specific post. It is commonly associated with parking (as in a vehicle being stationed in one spot) as well as with diplomatic or military personnel being posted abroad. The underlying sense is one of stopping and remaining fixed at a designated place.
On'yomi
ちゅう