Can I use my metric speedometer on I-19?

No, speed limits are still enforced in miles per hour. Only the distance and exit signs are metric.

Is there a toll on I-19?

No, I-19 is a toll-free highway, though international crossing fees apply at the border.

Where is the best place to wait for a border slot?

Most drivers use the staging lots on Mariposa Road or the truck stops in south Tucson if the delay is over 4 hours.

Interstate 19 (I-19) Trucking Guide: Routes, Fuel, Stops & Compliance

I-19 Trucker’s Guide: Navigating the Metric Corridor

Interstate 19 is one of the most unique stretches of asphalt in the American Southwest. Connecting the Mexican border at Nogales to the major logistics hub of Tucson, this 63-mile (102 km) stretch is the only interstate in the U.S. that primarily uses the metric system for its signage.

Overview and States Covered

Interstate 19 (I-19) is a north-south intrastate highway located entirely within the state of Arizona. It serves as a vital international trade link, funneling thousands of commercial vehicles daily from the Mariposa Port of Entry into the heart of the United States via Interstate 10.

States Covered: Arizona.
Total Distance: 63.35 miles / 101.95 kilometers.
Primary Purpose: International commerce, local agriculture transport, and commuter transit between Santa Cruz and Pima counties.

Unique Local Information and Miles

The most striking feature for any driver hitting I-19 is that distances are posted in kilometers. While speeds are still posted in miles per hour (MPH), the exit numbers and distance-to-city signs follow the metric system, a relic of a 1970s pilot program.

Nogales (KM 0 / Mile 0): The starting point at the Mexican border.
Rio Rico (KM 17 / Mile 10): A growing community with significant local truck traffic.
Tubac (KM 34 / Mile 21): A historic arts colony; watch for slowing tourist traffic.
Sahuarita/Green Valley (KM 63-75 / Mile 39-46): Home to massive open-pit copper mines and pecan orchards.
Tucson (KM 102 / Mile 63): The northern terminus where I-19 merges with I-10.

Trucker Pain Points and Solutions

The short length of I-19 is deceptive; it packs high-intensity challenges into its 63 miles. From international paperwork to shifting climates, here is how to handle the "Metric Highway."

Pain Point: Metric Confusion.
Solution: Don't let the "100" signs fool you—you aren't 100 miles from Tucson, you're 100 kilometers (about 62 miles). Use your ELD or GPS set to miles if you find the math distracting during heavy traffic.

Pain Point: Border Inspection Delays.
Solution: The Nogales port can back up for hours. Always check the CBP Border Wait Times before arriving. Ensure your manifest is digital and ready to speed up the process.

Unique Hazard Narrative: The "Pecan Crosswinds"

Between Sahuarita and Green Valley, the highway is flanked by the world’s largest irrigated pecan orchard. These trees create a "tunnel effect" that abruptly ends, hitting high-profile trailers with sudden, violent crosswinds. When you exit the sheltered tree line, be prepared for a 20-30 MPH gust that can shift your lane position instantly.

Unique Driving Strategy: The Checkpoint Coast

Northbound I-19 features a permanent U.S. Border Patrol checkpoint around KM 42 (Mile 25). The strategy here is "early deceleration." Do not wait for the lights; begin coasting and downshifting a mile out. Heavy braking near the checkpoint with a full load of Mexican produce can lead to brake glaze or shifted cargo, especially if you're directed to the secondary inspection area.

Unique “Local Insider” Insight

If you are looking for a break, skip the crowded stops in Tucson. The Tubac Golf Resort area (Exit 34/40) has nearby shoulder space that is much quieter. Also, keep an eye on your fuel; prices in Nogales are often inflated due to border proximity. It is almost always cheaper to fuel up in South Tucson near the I-10/I-19 interchange.

Common Mistakes and How to Avoid Them

The biggest blunder on I-19 is speed management in the "Metric Zone." Drivers often see "Exit 100" and assume they have time for a long break, only to realize they are much closer to their destination than thought.

Mistake: Overestimating Distance.
How to Avoid: Remember the 0.62 rule. 1 Kilometer = 0.62 Miles.
Mistake: Ignoring the "Metric" Speed Trap.
How to Avoid: Local police are very active near Rio Rico. Just because the distance signs are metric doesn't mean the speed limit is. Stick strictly to the posted MPH signs.

Mile Marker Guide (Metric vs. Imperial)

Use this comparative scale to keep your HOS logs and arrivals accurate while traveling the only metric interstate in the nation. It helps bridge the gap between your odometer and the highway signage.

KM 0 / Mile 0: International Border, Nogales.
KM 12 / Mile 7: Mariposa Road (Major Truck Route).
KM 42 / Mile 26: Border Patrol Checkpoint (Northbound).
KM 63 / Mile 39: Sahuarita Road.
KM 101 / Mile 63: I-10 Interchange (Tucson).

Trucking Compliance: Form 2290

Operating on a major international corridor like I-19 means frequent inspections. Arizona DOT officers will verify your Heavy Vehicle Use Tax (HVUT) status during random pull-ins.

To avoid being sidelined at the port or a mobile scale, make sure you e-file form 2290 to receive your Watermarked Schedule 1 immediately. You cannot register or renew a commercial vehicle in Arizona without this proof of filing.

Truck Stops with Exact NAP

Tucson serves as the primary service hub for I-19. These locations offer full services including scales, showers, and ample overnight parking.

Love's Travel Stop #620
Address: 1000 W Belmont Rd, Tucson, AZ 85705
Phone: (520) 293-4554

TravelCenters of America (TA) - Tucson
Address: 5451 E Benson Hwy, Tucson, AZ 85706
Phone: (520) 574-0010

Truck Parking with NAP

Parking is limited on this short route. The following locations are recognized for commercial vehicle staging and legal rest periods.

Canoa Ranch Rest Area (Northbound)
Address: I-19 Milepost 32, Green Valley, AZ 85614
Note: This location features automated truck parking sensors to show availability.

Mariposa Port Commercial Parking
Address: 200 N Mariposa Rd, Nogales, AZ 85621

Weigh Stations with NAP

All commercial traffic crossing into the United States must stop at the Port of Entry. Additional inspection points are located further north along the corridor.

Canoa Ranch Inspection Site
Address: I-19 KM 42 (Northbound), Green Valley, AZ 85614

Nogales Port of Entry (Mariposa)
Address: 230 N Mariposa Rd, Nogales, AZ 85621
Phone: (520) 287-1410

Truck-Friendly Restaurants & Indian Food

Finding a balance between local flavors and driver-friendly accessibility is easy with these recommendations along the Tucson-Nogales corridor.

Wisdom's Cafe (Famous Fruit Burritos)
Address: 1931 Frontage Rd, Tumacacori, AZ 85640
Phone: (520) 398-2397

Sher-e-Punjab (Indian Cuisine)
Address: 853 E Grant Rd, Tucson, AZ 85719
Phone: (520) 624-9305
Note: Plenty of nearby street parking for bobtails.

24/7 Truck Repair with NAP

When breakdowns happen in the desert, quick response times are vital. These mobile and shop-based services specialize in heavy-duty emergency repair.

TRP Truck Repair Tucson
Address: I-19 Exit 102, Tucson, AZ 85706
Phone: (928) 380-4762

Roadside Systems 24/7
Address: Mobile Service Only (Tucson/Nogales Corridor)
Phone: (520) 624-1100

Truck Parts & Accessories with NAP

Whether you need major components or driver comforts, these suppliers in the Tucson area offer the widest inventory for the I-19 region.

FleetPride
Address: 2202 S 4th Ave, Tucson, AZ 85713
Phone: (520) 622-4411

Vanguard Truck Centers
Address: 1400 E Benson Hwy, Tucson, AZ 85714
Phone: (520) 623-9515

EV Charging and Gas Stations

Alternative fueling is expanding along the Arizona border region. These stations provide standard diesel and newer charging infrastructure for mixed fleets.

Tesla Supercharger - Sahuarita
Address: 15930 S Rancho Sahuarita Blvd, Sahuarita, AZ 85629

QuikTrip (QT) - Diesel/Gas
Address: 3950 S Palo Verde Rd, Tucson, AZ 85714

State-by-State Fuel Tax (IFTA) & Price Insights

Arizona’s diesel tax for 2026 is $0.26 per gallon. Because I-19 is short, most drivers "top off" in Tucson where prices are competitive due to high volume.

Avoid buying fuel at the very last station before the border in Nogales, as you will pay a premium of $0.15 to $0.20 per gallon. Check current rates at the Arizona Department of Transportation.

High Traffic Zones

While much of I-19 is rural, the endpoints are prone to congestion. Plan your transit times to avoid these specific areas during peak hours.

Valencia Road (Tucson): Heavy merging traffic from the Tucson International Airport area.
Nogales (Mariposa Rd): Expect gridlock between 2:00 PM and 6:00 PM when produce trucks are cleared from the port.

Terrain Warning, Cell Signal, and Dead Zones

Mostly flat desert, but there is a steady 2,000-foot elevation gain as you move north from Nogales to Tucson. The open terrain is generally good for connectivity.

Terrain: Steady incline Northbound. Watch for shifting grade near KM 20.
Cell Signal: Excellent 5G coverage throughout the corridor.
"Dead Zone" Alert: There are very few literal dead zones on I-19, but signal can drop momentarily near the KM 38 (Mile 23) markers due to local topography near the Tumacacori mountains.

Port-Specific Compliance

The Nogales-Mariposa Port of Entry is the primary commercial gate. You must have your Customs and Border Protection (CBP) decals up to date.

Arizona also requires a valid Single State Registration System (SSRS) or the current UCR filing for all interstate carriers crossing this line. Check current regulations on the Arizona Port of Entry website.

Exit Information Table

A quick-reference guide for navigating the unique metric exits of I-19. Keep this handy for planning your stops.

Exit (KM)	Destination	Major Services
4	Mariposa Rd (Nogales)	Border Port, Customs
34	Tubac	Historic Site, Parking
63	Sahuarita Rd	Gas, Food
101	I-10 West (Phoenix)	Full Logistics Hub

Weather, Wind, and Rules

Summer temperatures regularly exceed 105°F. Winter is mild, but "Monsoon Season" (July-September) brings flash floods that can submerge frontage roads.

Weather: Heat monitoring is essential for tire and engine health. See National Weather Service for Phoenix/Tucson.
Wind Advisory: High wind warnings are common in the Canoa Ranch area.
State Rules: Arizona is a "Move Over" state. You must move over for any vehicle with flashing lights on the shoulder.