Imagine you're playing with a bunch of clay, and you create a small hill or bump with it. Now, let's say you took a stick or pencil and poked the top of the bump to create a small hole. This hole is called a dale.
In real life, a dale is a small valley or depression in the ground. It usually occurs between two hills or mountains and is formed by natural forces, such as erosion caused by water or ice.
So essentially, a dale is like a little divot in the ground, created by nature over a long, long time.