One's first instinct when hearing the word "journey" may be to assume said journey is a journey with only physical components. However, it is very rare for a journey to only have physical components. Generally a journey will consist of a combination of physical and mental elements, and depending on the story being told, one may be more accentuated than the other.

In Siddhartha, the mental component of the journey is more accentuated than the physical, as Siddhartha's main goal is to reach enlightenment: a predominantly mental state. Physical componments of this journey are what challenge him the most, as they bring Siddhartha farther away from his goal.

Below is a Stupa surrounded by the 12 stages of the Hero's Journey -- starting at the Ordinary World, and ending at Return with the Elixir. Each box is clickable. When clicked, you will be redirected to a page with detail on the stage you clicked.

Further below is a table describing the Four Stages to Enlightenment, and how one may be able to obtain them. This table will be referenced in how far Siddhartha is to obtaining enlightenment, and Nirvana, during his journey.

Stupas were built of stones or bricks to commemorate important events or mark important places associated with Buddhism or to house important relics of Buddha.

The Four Stages of Enlightenment

stage's "fruit"	abandoned fetters	rebirth(s) until suffering's end
stream-enterer	identity view (Anatman), doubt in Buddha, ascetic or ritual rules	up to seven rebirths in human or heavenly realms
once-returner	identity view (Anatman), doubt in Buddha, ascetic or ritual rules	once more as a human
non-returner	sensual desire, ill will	once more in a heavenly realm (Pure Abodes)
arahant	material-rebirth desire, immaterial-rebirth desire, conceit, restlessness, ignorance	no rebirth

Siddhartha's Heroic Journey

The Four Stages of Enlightenment