The King’s Highway was a trade route of vital importance to the ancient Middle East. It began in Egypt, and stretched across the Sinai Peninsula to Aqaba. From there it turned northward across Jordan, leading to Damascus and the Euphrates River.
Here is a link to information you will find useful in answering your question:
http://en.wikipedia.org/wiki/King's_Highway_(ancient)
I hope you have found this helpful.
God bless,
Mike