In what city and present day county was the relief of Alexander the Great found?

I wonder whether you meant any specific relief in particular?

I know of some reliefs of Alexander, on the Alexander sarcophagus. This sarcophagus, dating back to 4th century BCE, so from the time of life of Alexander, included some reliefs of him, and was found in Sidon, in today's Lebanon, on the coast of the Mediterranean.