First draw a stick figure for Conall, wearing his horned hat. Then draw a spiral, starting over his head, through his middle, around twice, stopping just before his legs, and close off the spiral. This is the long serpent passing through his waist belt. (Don't draw the coils of the snake too close together).
Now erase the bottom piece of the snake that crosses the figure, and erase the legs. (Conall slips the snake out of his belt and leaves the fortress).
But where is the fortress? That comes next. First build the outer walls. Start a line at the bottom of the stick and follow the curve all the way around. Turn into the fortress and follow the inside curve around.
Just two inside walls to draw now. First, start at the beginning of the snake. Go down then up and over the top of the hat. Start a new line at the very top of the hat. Go down then, up over the line you just drew. Carefully erase the horns from the hat and the fortress is complete.
This is a traditional Camonica Valley Maze. This and other mazes can be found in the book Celtic Design: Maze Patterns by Aidan Meehan.