AMP: 249 Location: I-90 and MT-55, Jefferson Cty Reassurance shield after the 55 interchange. AMP: 255 Location: I-90 and S-359, Jefferson Cty A few miles later, we’ll approach Secondary 359. AMP: 256 Location: I-90 and S-359, Jefferson Cty Exit for Secondary 359, which heads south to Cardwell and north to Boulder via MT-69. Montana 2 … Continue reading Interstate 90, MT-55/S-399 to MT-2/S-359