U.S. Highway 87 (US 87) is a north–south United States highway (though it is signed east–west in New Mexico) that runs for 1,998 miles (3,215 km) from northern Montana to southern Texas, making it the longest north-south road to not have a "1" in its number and the third longest north-south road in the country, behind U.S. 41 and U.S. 1. Most of the portion from Billings, Montana to Raton, New Mexico is co-signed along Interstates 90 and 25. It is also co-signed along the majority of I-27 in Texas and future plans call for the interstate to be extended along the US 87 corridor. As of 2004, the highway's northern terminus is in Havre, Montana, at US 2 and its southern terminus is in Port Lavaca, Texas, at SH 238.