It's called a loop-hole or sometimes an arrow loop
An opening in any type of fortification wall, usually shaped like a key hole, vertical slit or cross, that allows an archer to fire his weapon with a great amount of protection.
An arrowslit is a slit, such as can be seen in a castle wall, through which arrows can be fired.
these fortifications were called ringworks, the castle's primary defense against attack
Castle loop holes are narrow vertical slits in the castle wall that allowed bowmen to shoot arrows at the enemy while making it difficult for the enemy to shoot into the castle.
The wall of a castle is a stone wall that protects the castle from invaders
It was a chicken horse
Crenellations is on the top of the castle wall, and looks like a sawtooth pattern. The teeth are called Merlons, and the gaps between are called embrasures.
I do not flaming well know that is why i asked this question.
A battlement is a wall that has openings like vertical slots at the top for archers to shoot through.
Battlements? You may need to be more specific, there are kind of a lot of things on castle walls...
When they were built they would have been called a bucket or a ole in the wall. today they are called toilets.
It Is A High Wall Which You Go Up To Walk On It. The View Is Incredible!!