I've lived in Japan about 15 years now and have moved around quite a bit. One thing in common is that the 5 cities I've lived in all have (or had) a castle. I started in Matsuyama which is, in my opinion, the best castle (of these 5). After that I was in Okayama, Shibata (Niigata Pref.), Sendai (Aoba) and now Odawara. I live just a couple minutes walk from the castle and get to pass it every day I go to work or the station. In the spring time, the more than 350 sakura trees make it one of the "Top 100 Cherry Blossom viewing places in Japan". Odawara Castle is also the nearest castle from Tokyo (35 minutes by bullet train), so we get quite a few tourists (including foreigners) visiting every day. Odawara is also the city I've lived the longest here in Japan (approaching 6 years). It's a great place to live with it's proximity to both the beach and mountains and to Tokyo. The best castles I've been to are Himeji which is the largest and most visited castle in Japan and Matsumoto which not only has the best name but is also a beautiful black castle. :) Pictures above are Matsuyama Castle and cherry blossoms at Odawara Castle.