Have you seen these hills all over the country? They are mottes: man-made mounds created by the Norman invaders over 800 years ago. They built a wooden castle on top of the mound, called a keep. Alongside this, a little town called a bailey was built on a flat man-made plain, enclosed by a wooden fence. They could see for miles around to defend from native attackers. A ditch was dug all around for extra protection, to slow attackers down. Later, stone castles replaced the wooden ones on top of t