Our friend Liz Suenaga introduced this charming, concise piece on stone walls (石垣, ishigaki). Kumamoto is composed of them, from the agriculture retaining walls in the mountains to the ancient bridges to, of course, the castle. They all have absorbed centuries of time and reflect it back.
One point the article doesn’t mention is their durability - practically infinite - compared to concrete, which will last a mere few decades. Stone masons recently widened the Shirakawa banks, painstakingly, shaping each rock to fit by hand with chisels. It took a long time to finish and was expensive in the short term, but my great-great-great grandchildren will likely see it. - William