Fukuoka Castle Ruins

This guide to Fukuoka Castle Ruins follows a 2024 discovery: a letter unearthed at the Fukuoka City Museum, written by a Kuroda retainer in the 1640s, that upended four centuries of belief about these dry-stacked stone walls. You'll hear how lord Kuroda Nagamasa's crews rushed the castle up between 1601 and 1607 using recycled stone and ordinary laborers rather than trained masons, and how the walls still earned the castle its nickname, the Stone Castle. It points out the ya ana wedge holes and the oversized kagami ishi stones near the gates worth looking for as you walk the ruins.