Yagura

The word yagura comes from ya, meaning "arrow", and kura, which means "storehouse." As this would indicate, yagura were used to store arrows... along with all other kinds of weapons, food, and supplies. Some yagura also housed soldiers and even, in rare cases, the daimyo and his family. In addition to being storehouses, yagura also served as important defensive structures. Usually built atop ishigaki (stone walls), they were ideally situated to be used as watchtowers. This high position also made them very effective points from which to stage defensive attacks.

Yagura come in all shapes and sizes, but most can be grouped into one of two broad categories: sumi-yagura and tamon yagura. The distinction is easy to make; sumi-yagura are tower-shaped, and can be anywhere from one to three stories high. Tamon yagura, on the other hand, are long and thin, looking more like walls than towers. Let's take a more detailed look at both:

Sumi-yagura were usually constructed at strategically important corners within the defensive scheme of a castle (the word sumi means "corner"). The corners were important points of defense in that they were the easiest spots for attackers to climb up. Sumi-yagura were the perfect solution to this problem; like tenshu, sumi-yagura usually had ishi-otoshi (rock chutes) built into the corners. Invaders would have to try to find a more suitable place along the ishigaki to climb. Or better yet, they would be forced to navigate the complex maze of castle walls and gates if they wanted to advance further.

Most tamon yagura have only one story, and are often attached at either end to a sumi-yagura. They are essentially covered galleries from which archers and musketeers could line up and fire at the enemy while being relatively protected. Tamon yagura provided a much stronger and more formidable defense than simple unmanned walls and moats, while remaining easier to build and maintain than sumi-yagura.

Yagura often employed defensive features with other castle structures. Like normal walls

Yagura Mon

The yagura mon is a special type of structure. A cross between and yagura and a gate, yagura mon are usually found at the inner openings of masugata. They are usually two stories high; the first story is the gate itself while the second is used for storage and as a defensive station. This deadly combination made the yagura mon a difficult point of entry for would-be attackers.