Standing in the centre of the city is never usually this peaceful and I find myself peering down into a tiny patch of still water, protected by a hefty, 800-year-old, tiered, black-lead roof. This is Kinjo Reitaku, a well which sits in a small secluded corner of one of Japan’s most revered gardens. It’s also the origin of the once formidable town, which radiates like an overflowing spring around it.