Zim Zim Falls Trail is an old dirt road that heads west from Berryessa Knoxville road (mile marker 24) approximately 3.5 miles to the Zim Zim waterfall. The trail crosses  Zim Zim Creek numerous times, so when the creek is running be prepared to get wet. Zim Zim waterfall cascades down approximately 100 feet and is a fabulous place to stop and enjoy a snack.