AMP: 19 Location: US-89 and East River Rd, Park Cty Reassurance shield after the S-540 junction. AMP: 7 Location: US-89 and East Gate Rd, Corwin Springs, Park Cty A few miles later, we’ll pass by the community of Corwin Springs. AMP: 1 Location: Scott St and Hellroaring St, Gardiner, Park Cty A few miles later, we’ll enter unincorporated … Continue reading U.S. Route 89, S-540 to Yellowstone National Park (TO US-14/US-16/US-20/US-89/US-191/US-212/US-287)