Tumbleweed Hill is the BIG hill on 2222 after you turn off 620. If you were coming from Mansfield Dam and turned right onto 620 you would hit a big downhill. That is Tumbleweed Hill. There used to be a restaurant at the top called the Texas Tumbleweed, hence the name (a little Austin trivia- hehe). My daredevil husband got to 55 mph last time going down it. I am a little more timid and feathered the brakes.