AMP: 0 Location: 1st Ave and Walnut St, Big Timber Reassurance shield as 191 flies solo for the first time since Bozeman. AMP: 1 Location: US 191 and Howie Rd, Sweet Grass Cty As we head out of Big Timber, turn right for unsigned 478, which heads down a gravel road towards Howie  N to US-12, S … Continue reading U.S. Route 191, I-90 Bus to S-478