bridle path

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A trail for horseback riding.

from The Century Dictionary.

• noun A path which is wide enough to be traveled on horseback, but not in a carriage. Also bridleway.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun An established trail used by riders mounted on horses.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun a path suitable for riding or leading horses (but not for cars)