As I understand it, the Temple of Time contains a portal to the Sacred Realm:

Seven years ago, Ganondorf, the
King of Thieves, used the door
you opened in the Temple of Time
and entered the Sacred Realm.

also,

Legends say that the Temple of
Time is the entrance to the
Sacred Realm...
Did you know that?

this portal probably links directly to the Temple of Light, which is in the Sacred Realm. I believe that Zelda is the Sage of Time (patron of the Temple of Time in Hyrule; Rauru is the Sage of Light, patron of the Temple of Light in the Sacred Realm) but I do not have any evidence for Zelda's temple. This shows that she is a sage:

And the other, who holds the
Triforce of Wisdom...
is the seventh Sage, who is
destined to be the leader of
them all...

but does not tell her temple.