If Plato's line analogy is regarded as a map, then indeed his allegory of the cave could be described as the actual journey. When Plato wrote "The Republic" he became Socrates most enlightened pupil. As they both dreamed of an almost utopian existence for all societies or "states". They both believed that the first key to having an ideal state or communatable existence is enlightenment of ones state of being. The highest state being the "Chief Good".
If the most important step to enlightenment is education, then Plato's statement "It is like a line divided into unequal sections- is in actuality a roadmap to the "Chief good" and his allegory of the cave is an example of the journey itself needed to be taken to reach this ideal state of education.
We start with the line (map). It is divided into two unequal sections. The lower and smaller section being dominated by the sun as it consists of objects, and images as seen by you"re eyes but not necessesarily understood by your mind. This section also consists of beliefs; which sometimes are pressed upon us by the generations before us. Someone's opinion decades ago, becomes our beliefs today, and in a sense our beliefs are fictional or at least fraudulent. This smaller section of the line is lacking the size of the upper because it is of less importance than the upper. The upper of course is dominated by the ideal state of being the "Chief Good". Consisting of intellectual states and forms, which are understood, in a more geometrical figure. Which of course leads to understanding and intelligence and the most important of all knowledge. Using this line Plato was drawing out a map for us to follow.
Following Plato's line is only half the battle. He drew the road map now we must make the journey, the most difficult part of reaching enlightenment. Plato uses the allegory of the cave to guide us through the journey. Plato describes a group of people in a cave, with one end open, and the other closed with a fire that cast their shadows on the wall.
