AMP: 20 Location: US 89 and S-431, Cascade Cty Reassurance shield after 431 and 565 as we enter Cascade County AMP: 20 Location: US 89 and S-431, Cascade Cty 20 miles to junction I-15 AMP: 7 Location: US 89 and MT 200, Cascade Cty 13 miles later, we’ll approach Montana 200. AMP: 7 Location: US … Continue reading U.S. Route 89, S-431/S-565 to MT-200