The western reaches contain rank after rank of forested ridges, extending to the jagged wall of the Karpash Mountains. The Road of Kings, a major trade route, passes through central Corinthia.
Corinthia has a separate identity as early as the florescence of Acheron. It was subject to the latter, then "gained its independence" with the fall of the ancient empire to the Hyborians.
Some time during the 3000 years that followed, it came under the growing hegemony of the Hyborians. The economy of Corinthia may have been both pastoral and agricultural, with specialized small industries in the city-states.
References: Hyborian Age I-II, Rogues in the House, Shadows in the Moonlight, Jewels of Gwahlur, Conan the Great.