"Out of the beaten track" is a phrase used to describe something or somewhere that is off the usual or common path. Synonyms for this phrase include "off the grid," "off the beaten path," "off the beaten trail," "off the main road," "off the established routes," "out of the way," "remote," "untrodden," "undiscovered," "unconventional," "unfrequented," "isolated," "secluded," and "hidden." These words can be used to describe places like mountains, forests, or beaches, or ideas that are not widely accepted or explored. Using these synonyms can add color and variety to your writing, and can help you convey ideas with precision and nuance.