Most moats at castles these days where the walls are not lined with stone are covered in grass and shrubs to prevent erosion. Originally, these walls may or may not have been covered in grass. Simple walls of packed mud and clay would have been much more difficult for any attackers to climb but would have also been prone to erosion. In the case of plain mud walls, the angle of the wall was cut to about 45' to prevent too much erosion. They also mixed in clay to make the walls stronger and to make them slippery for anyone trying to climb up. In the case of grass covered walls the angles were sharper at 60' to make them more difficult to climb. You can see examples of both types in the moats pictures at the top of the page.
All Stone Lined Pictures (70)
Matsushiro Castle
Matsushiro Castle
Iga Ueno Castle
Iga Ueno Castle
Iga Ueno Castle
Iga Ueno Castle
Iga Ueno Castle
Shoryuji Castle
Shoryuji Castle
Yamato Koriyama Castle
Yamato Koriyama Castle
Yamato Koriyama Castle
Yamato Koriyama Castle
Yamato Koriyama Castle
Matsumoto Castle
Morioka Castle
Ako Castle
Ako Castle
Ako Castle
Ako Castle
Fukui Castle
Kanazawa Castle
Kanazawa Castle
Kanazawa Castle
Kumamoto Castle
Sunpu Castle
Kofu Castle
Kofu Castle
Yamagata Castle
Odawara Castle
Edo Castle
Edo Castle
Edo Castle
Edo Castle
Edo Castle
Hikone Castle
Hikone Castle
Hikone Castle
Hikone Castle
Aizu Wakamatsu Castle
Aizu Wakamatsu Castle
Matsumoto Castle
Matsumoto Castle
Matsumoto Castle
Nagoya Castle
Nagoya Castle
Nagoya Castle
Nagoya Castle
Nagoya Castle
Nijo Castle
Nijo Castle
Nijo Castle
Nijo Castle
Osaka Castle
Shirakawa Castle
Tsuchiura Castle
Tottori Castle
Matsue Castle
Matsue Castle
Akizuki Castle
Odawara Castle
Odawara Castle
Odawara Castle
Odawara Castle
Odawara Castle
Nagashino Castle
Yoshida Castle
Yoshida Castle
Yoshida Castle
Akashi Castle