most initiation rituals take place in a confined dark space, usually underground and in compete solitude

the mind projects fears of which the individual has to overcome after which the individual comes out to the light blessed with insight of self
(a lot like yoda's cave, not to mention the coffin of snb)

Speaking of dark and rituals, just found this link on another site. Still looking around, but lots of "interesting" reading there:

[link to www.goroadachi.com]