(population: 38,000) Korthos is the second largest city in the kingdom of Serathyr and one of the oldest cities on Corwyn.

Korthos is located in northern Serathyr, nestled between the southern shores of the Sea of Alyr and the northern edge of the Cairn Mountains. The city has its roots back in the Human realm of Asgamoth of the late Third Age.

The city is very busy with the overland trade to and from the seaport of Rastios, marine traffic from the Sea of Alyr, as well as lumbar shipments from the Celadon Forest. The city of Korthos is accessible from both the north and south via the Olde Peninsula Road, which runs northeast to Castle Celadon and south to the seaport of Rastios.

The city of Korthos is currently governed by Duke Axel Arkalan.