Layout of Piedras Negras
Piedras Negras stands at about 220 m on the south bank of the Río Bravo, on rolling brush country at the north-eastern corner of Coahuila. It was founded in 1850 as a military colony called Villa de Herrera, two years after the treaty that fixed the border on the river, and took the name Piedras Negras — black stones, for the coal seams outcropping nearby — soon afterwards. Between 1888 and 1911 it was called Ciudad Porfirio Díaz, and it reverted to its older name at the Revolution. The 2020 census counted about 163,600 people in the municipality, making it the fourth-largest city in the state after Saltillo, Torreón and Monclova.
The centre is a compact grid a few blocks back from the river, built around the Plaza de las Culturas and the parish church, with the old customs house and the approach to Bridge 1 at its northern edge; the shops on the streets leading to the bridge trade largely with visitors from Texas. The Libramiento ring road carries through traffic around the south and west, and the industrial parks and the Camino Real bridge approach lie downstream on the eastern side. Piedras Negras International (PDS) is a small field a few kilometres south of the centre with a limited domestic schedule; most air travellers use Eagle Pass and the Texas network, or drive four hours to Saltillo and Monterrey.
Distances from Piedras Negras
| Place | km | Time | How |
|---|---|---|---|
| Eagle Pass, Texas (Bridge 1) | 2 | 15 min | On foot or by car, plus queue |
| Piedras Negras airport (PDS) | 6 | 10 min | Taxi |
| Nava and the Carbón power stations | 30 | 25 min | MX-57 south |
| Ciudad Acuña | 55 | 45 min | MX-2 north-west along the border |
| Nueva Rosita | 130 | 1 h 30 | MX-57 south |
| Monclova | 190 | 2 h | MX-57 south |
| San Antonio, Texas | 230 | 2 h 15 | US-57 and I-35 from Eagle Pass |
| Nuevo Laredo | 245 | 3 h | MX-2 south-east |
| Saltillo | 400 | 4 h | MX-57 south |
| Monterrey | 435 | 4 h 30 | MX-57 and MX-53 via Monclova |
The crossings and the coal basin
Two bridges connect Piedras Negras with Eagle Pass. Bridge 1, the original crossing at the end of the main street, takes pedestrians and cars into the centre of the Texas town; the Camino Real International Bridge, opened in 1999 about 3 km downstream, carries the commercial trucks and the through traffic between Highway 57 and US 57. A rail bridge runs alongside them: the line here was completed in 1883 and was for decades the principal railway link between Mexico and the United States, which is why the town grew where it did. Compared with Nuevo Laredo, 245 km downstream, the freight volumes are modest, but the crossing is the shortest road route from San Antonio into central Mexico and Highway 57 runs unbroken from here to Mexico City. The border map places it among the other ports of entry.
Behind the city lies the Sabinas basin, the only substantial coalfield in Mexico. Mines around Nava, Múzquiz, Sabinas and Nueva Rosita, strung along Highway 57 south of Piedras Negras, have worked since the 1880s and still supply the two Carbón thermal power stations at Nava, 30 km away, which burn Coahuila coal to feed the northern grid. Coal also fed the steelworks at Monclova, 190 km south, and the whole corridor between the border and Monclova is industrial rather than agricultural. Maquiladora plants on the eastern edge of Piedras Negras add electronics and vehicle components to the export traffic.
The city is landlocked and about 500 km from the nearest sea, so it has no beach; the local water is the Río Bravo itself, and the reservoir behind the Amistad dam lies 60 km upstream past Ciudad Acuña. Piedras Negras is also where nachos are said to have been invented, in 1943, by Ignacio Anaya at a restaurant serving customers from the US air base at Eagle Pass — the dish took his nickname, and the city marks it with an annual festival. South and west the country opens into the semi-desert of northern Mexico; the road map shows Highway 57 running the length of it.
Questions about Piedras Negras
Where is Piedras Negras on the map of Mexico?
On the Río Bravo in north-eastern Coahuila, at 28.70° N, 100.52° W. It is about 190 km north-east of Monclova, 245 km north-west of Nuevo Laredo and roughly 400 km from Saltillo on Highway 57.
Which US city is across the border from Piedras Negras?
Eagle Pass, Texas. Two international bridges join them: Bridge 1 in the centre of both towns, and the Camino Real International Bridge, opened in 1999 downstream, which handles the commercial traffic.
Were nachos invented in Piedras Negras?
The city claims them. In 1943 Ignacio Anaya, a maître d' known as Nacho, is said to have improvised tortilla chips with melted cheese and jalapeños for a group of customers from Eagle Pass. Piedras Negras holds a nacho festival each October.
Is Piedras Negras safe to visit?
Coahuila has for several years carried one of the lower US State Department advisory levels among the border states, though restrictions apply in parts of it. Check the current advisory before travelling.