2,500 year old lost Persian army found

[Robert Vermaat]

....my point being that not many Persian armies numbering in the thousands set off for Siwa during that period.....

Well, we also thought that we knew from the available sources than no Roman armies ventured very far east into Germany after the early 1st century. And lo and behold, there's that new battlefield than no-one believed could exist.

Jona is right, the sources cannot be trusted to descrive all and everything.

There may have been numerous expeditions into the western desert about which we do not know.

Isn't there a find in the Himalaya of a group of people (army?) surprised by the weather and reduced to bones?