The men of Gibeon sent to Joshua to the camp to Gilgal, saying, Don't slack your hand from your servants; come up to us quickly, and save us, and help us: for all the kings of the Amorites that dwell in the hill-country are gathered together against us.
As soon as Joshua received the plea from Gibeon, he commanded an all-night moonlight march.  We know it was a moonlight night because, the next morning Joshua could see the sun in the east over Gibeon and the moon not yet set over the valley of Aijalon to the westward.  The coalition were encamped west of Gibeon, and by his surprise march, Joshua was able to throw his army squarely between the would-be-attackers and Gibeon.  He proceeded to chase them in a northwesterly direction down a very rocky and precipitous road through Upper Beth-horon and Lower Beth-horon.  As Unger said: