Koso Mura, being near where the pass through the Taru Mountains lets out into the heart of Naishou Province, was the site of the province's first fortification. The castle, Jimichi, has been repaired and improved upon over the centuries and it remains a formidable bastion and line of defense. Unfortunately for the province, the Itochu River became more easily navigable about 200 years ago and now invading armies can come from the south as well as through the mountains. Indeed, 2 of the 3 Great Clan armies now in the province came from the south and have ignored Koso Mura and the fortress completely. The keep is 3 stories and dominates the city. Any attackers must approach it through the narrow city streets, under fire the entire way. The barracks are sufficient to hold a legion (~1000 troops), but it typically houses much less. When the city is at peace, Jimichi Keep functions as the city's political center, as well.