over the river and through the woods

Etymology
Originally based on a Thanksgiving poem written by, this phrase was eventually turned into one of the many various Christmas carols and then soon developed its own meaning in the English lexicon. See the Wikipedia article for more information.

Prepositional phrase

 * 1)  Trying to achieve a particular task, often with difficulty.
 * 2)  Lost.
 * 3)  Having lost one's mind; insane.