Ryumyaku (ryoo-myah-koo) is a term from feng shui, the East Asian art of reading the land. It is usually translated as "dragon vein": a line along which the energy of the land, called qi (ki in Japanese), is said to flow.
Senso-ji Temple stands northeast of where Edo Castle stood. In Japanese tradition the northeast is the kimon, the "demon gate": not a gate you can walk through, but the direction from which misfortune was believed to enter. In 1590 Tokugawa Ieyasu chose it as his prayer temple, in part because it stands at the demon gate of Edo Castle. Its formal Buddhist name, Kinryu-zan, means "Golden Dragon Mountain".
We walk this ground slowly, and stop to breathe where the stories are set.