Interstate 25 in New Mexico

I-25 begins at I-10's exit 144 in Las Cruces (elevation 4,000 feet (1,200 m)),[3] just south of the New Mexico State University (NMSU) campus. I-25 is concurrent with US 85 at this point, and carries US 85 concurrently for the remainder of its run in New Mexico, save for a 4-mile (6.4 km) through Las Vegas where unsigned US 85 follows Interstate 25 Business (I-25 Bus., Business Loop 15) through the town. Immediately, the Interstate passes east of the NMSU campus, and the next three exits provide access to the city. The first exit is University Avenue, which provides access to NMSU. The final exit in Las Cruces is US 70.[4] Upon exiting the city, the speed limit increases by 10 mph (16 km/h) to 75 mph (121 km/h). Before I-25 reaches Truth or Consequences and just south of Elephant Butte Reservoir State Park, it crosses over to the west side of the Rio Grande.[5] From Las Cruces to Santa Fe I-25 follows the route of El Camino Real de Tierra Adentro.[6]

At the Big I in Albuquerque, New Mexico

South of Albuquerque near Socorro, it passes through the Bosque del Apache National Wildlife Refuge.[7] As I-25 nears Albuquerque, it has interchanges with roads such as US 380 and a concurrency with US 60.[8] State Road 6 (NM 6), the original US 66, meets up with I-25 in Los Lunas.[9] Just to the south of Albuquerque, I-25 enters Isleta Pueblo where it crosses back to the east side of the Rio Grande.[10]

I-25 in Albuquerque

The speed limit on I-25 in Albuquerque is 65 mph (105 km/h), except for one 1.5-mile (2.4 km) 55-mile-per-hour (89 km/h) section between Gibson Boulevard and Central Avenue. Through Albuquerque, I-25 is named the Pan American Freeway and there are frequent exits to city streets.[11][12]^: 248 A major interchange with I-40 (which is styled as the Coronado Freeway in the city) is named the Big I.[12]^: 248[13] It was given an honorable mention by the United States Department of Transportation and the Federal Highway Administration for excellence in urban highway design in 2002.[14]

Approaching Santa Fe, New Mexico, at sunset. The Sangre de Cristo Mountains, with snow, are in the background.

Sunset on I-25 at Santa Fe

Leaving Albuquerque, the 75-mile-per-hour (121 km/h) speed limit resumes as the freeway passes through Sandia Pueblo. After Bernalillo, I-25 passes through four more Indian Reservations (from south to north: the Pueblos of Santa Ana, San Felipe, Kewa, and Cochiti). I-25 turns to the northeast and away from the Rio Grande, alongside which it has run from its southern terminus, as it heads toward Santa Fe.[15] It climbs out of the Rio Grande Valley at a steep hill called La Bajada 11 miles (18 km) southwest of Santa Fe.[16]

Continuing 'northbound' at Santa Fe, I-25 heads southeast for approximately 45 miles (72 km), traveling through the Santa Fe National Forest and crossing Glorieta Pass (7,452 feet (2,271 m)).[17] It turns north again at Blanchard toward Las Vegas.[18] The highway maintains a north and northeast orientation as it leaves New Mexico traversing Raton Pass (7,798 feet (2,377 m)[19]) and enters Colorado. The speed limit through Raton Pass is 65 mph (105 km/h). From Santa Fe to Raton Pass, I-25 approximates part of the route of the Santa Fe Trail.[20] I-25 is 462.124 miles (743.716 km) long in New Mexico.[1]

I-25 in New Mexico currently has no auxiliary Interstates but it has six active business routes. The active business routes are located in Williamsburg–Truth or Consequences, Socorro, Belen, Las Vegas, Springer, and Raton. There was one other business route that was located in Santa Fe but was decommissioned.

• Media related to Interstate 25 in New Mexico at Wikimedia Commons