Yup, I agree, its more of an inner journey.
You could say something like:
"Name of text" by "Composer" traces a physical as well as a shared emotional journey in which the persona leaves childhood and enters adulthood.
The main thing is that is through this physical, nostalgic journey that he/she undertakes, through his/her memories, or something such as motifs, or particular events,it triggers the persona back into his/her childhood memories and allows him/her to understand this and this..etc
But, if you're talking of how one is physically journeying as the persona grows up, its somewhat harder to relate to inner journeys, because usually through inner journeys, you either go back into your past, or due to some spiritual or religious reason that you can actually embark upon the same physical journey, but a different spiritual inner journey.