Teraglen: The Journey Begins - Teraglen, #1

A secret land with a disturbing past. A growing threat lurking outside its borders. An unknowing voyager stumbles upon his fate - and he can't turn back... The lost land of Teraglen is far from being lost. It lies beyond the ocean, on the very edge of the earth - a secret realm, where monarchs rule from their thrones, protectors and protectresses defend the five cities against the East, and fly-darks and fly-lights, loyal beasts of war and transportation, guide their masters.
The last thing the Teras need is for an outsider to arrive - but he does - and his name is Daniel Marx. An audacious, young explorer from England, Daniel is determined to live up to his famous father's legacy. Ironically enough, discovering Teraglen is an accident (being led off course is easy enough when you're born curious). Unbeknownst to Daniel, Teraglen's enemy is awaiting his arrival. Daniel's curiosity leads him closer to the East, and he quickly finds himself on a dangerous quest - one he did not sign up for.