By road, San Nicolás de los Arroyos and Fray Marcos, Uruguay are about 427 miles (687 km) apart, or roughly 8 h 55 min of driving. You cross from Argentina into Uruguay at about mile 209, at the Gualeguaychú–Fray Bentos bridge.
Full advisory: Argentina, Uruguay. Advisory issued: Argentina July 10, 2026; Uruguay July 28, 2026; checked October 10, 2026.
On the roads, the State Department says:
- Argentina: “Drivers in Argentina tend to be aggressive, especially in Buenos Aires, and often ignore traffic regulations.”
- Uruguay: “If you are in an accident involving injury, stay in place until a police officer arrives.”
| Distance by road | 427 mi (687 km) |
|---|---|
| Drive time without stops | 8 h 55 min |
| Main roads, in order | RN9 → RN12 → RN14 → RN136 |
| Border crossing | about mile 209, Argentina → Uruguay (the Gualeguaychú–Fray Bentos bridge) |
| Regions on the route | Buenos Aires, Entre Ríos, Río Negro, Soriano, Colonia, San José, Canelones, Florida |
| Fuel estimate (car at 25 mpg) | about 17.1 gal; actual use varies by vehicle and traffic |
| Stops listed below | 8 |
Getting across the Argentina–Uruguay border
The route crosses at about mile 209, at the Gualeguaychú–Fray Bentos bridge, from Entre Ríos into Río Negro. Plan on two checks on each side: immigration for your passport and customs for the car.
| Entering Uruguay (U.S. citizens) | No visa needed for visits of 90 days or less. Passport: must be valid for 6 months beyond your arrival date. |
|---|---|
| Driving in Uruguay | You can drive on your U.S. license. |
| Entering Argentina (U.S. citizens) | No visa needed for visits of 90 days or less. Passport: must be valid when you enter; leave a blank page for the entry and exit stamps. |
| Driving in Argentina | A valid U.S. license usually works; an International Driving Permit is recommended. |
| Rental car | Cross only if the rental company authorizes it in writing and gives you the papers for the border; ask before you book. |
Sources: U.S. State Department, Uruguay (updated August 13, 2026); U.S. State Department, Argentina (updated July 16, 2026). Checked October 10, 2026; rules change, so confirm before you go.
How the San Nicolás de los Arroyos to Fray Marcos drive plays out
RN9 (90 mi) and RN12 (49 mi) carry about 33% of the 427 miles. The first 209 miles are in Argentina; the last 218 are in Uruguay. It runs through 8 regions: Buenos Aires, Entre Ríos, Río Negro, Soriano, Colonia, San José, Canelones, Florida. Of the 8 stops listed below, 4 are within a mile of the road.
Which roads connect San Nicolás de los Arroyos and Fray Marcos
| Road | Route miles (from–to) | Length, mi | Region |
|---|---|---|---|
| local roads | 0–4 | 4 | Buenos Aires |
| RN9 | 4–94 | 90 | Buenos Aires |
| connecting roads | 94–95 | 1 | Buenos Aires |
| RN12 | 95–144 | 49 | Buenos Aires, Entre Ríos |
| RN14 | 144–181 | 37 | Entre Ríos |
| local roads | 181–188 | 7 | Entre Ríos |
| RN136 | 188–207 | 19 | Entre Ríos |
| connecting roads | 207–209 | 2 | Entre Ríos |
| local roads | 209–306 | 97 | Río Negro, Soriano |
| connecting roads | 306–307 | 1 | Soriano |
| local roads | 307–343 | 36 | Colonia, San José |
| connecting roads | 343–346 | 3 | San José |
| local roads | 346–389 | 43 | San José, Canelones |
| connecting roads | 389–392 | 3 | Canelones |
| local roads | 392–427 | 35 | Canelones, Florida |
- Mile 115 of this route: Buenos Aires → Entre Ríos (region line)
- Mile 209 of this route: Entre Ríos → Río Negro (international border)
- Mile 226 of this route: Río Negro → Soriano (region line)
- Mile 307 of this route: Soriano → Colonia (region line)
- Mile 324 of this route: Colonia → San José (region line)
- Mile 368 of this route: San José → Canelones (region line)
- Mile 425 of this route: Canelones → Florida (region line)
Breaking up the drive: stops between San Nicolás de los Arroyos and Fray Marcos
- Right off the route (under 1 mile): Cathedral of Mercedes (mile 227), Teatro Macció (mile 344), Museo Departamental de San José (mile 344), Cathedral of Our Lady of Guadalupe (mile 378)
- Nature and outdoors: Ciervo de los Pantanos National Park (mile 98)
- Museums and history: Gualeguaychú Cathedral (mile 187), Cathedral of Mercedes (mile 227), Calera Real del Dacá (mile 227), Museo Departamental de San José (mile 344), Cathedral of Our Lady of Guadalupe (mile 378)
Ciervo de los Pantanos National Park
Marsh deer give their name to Ciervo de los Pantanos National Park, a Ramsar Site in Campana, Buenos Aires province, where waterbirds are abundant.
Gualeguaychú Cathedral
St. Joseph's Cathedral, also called Gualeguaychú Cathedral, serves as the cathedral church of the Roman Catholic Diocese of Gualeguaychú in Argentina.
Frigorífico Anglo del Uruguay
Part of a UNESCO World Heritage landscape inscribed in 2015, the old Anglo meatpacking plant stands on the Uruguay River at Fray Bentos, where frozen meat shipments began in 1924.
Cathedral of Mercedes
Since 1960, the Diocese of Mercedes has had its seat at the Cathedral of Our Lady of Mercy, the main Catholic church in this Uruguayan city.
Calera Real del Dacá
On the eastern edge of Mercedes beside the Dacá stream, the ruins of the Calera Real lime works date to 1722 and are considered the region's first industrial site; recent works added visitor circuits, lighting and interpretive signs.
Teatro Macció
San José de Mayo's Teatro Bartolomé Macció is a traditional theater, regarded as the city's most important building architecturally and declared a Historic Monument of Uruguay in 1984.
Museo Departamental de San José
Set in central San José de Mayo, the Museo Departamental de San José is a history and fine arts museum that also runs a library, archives and cultural programs.
Cathedral of Our Lady of Guadalupe
Construction of Canelones' Cathedral of Our Lady of Guadalupe began in 1816; the church became a cathedral in 1961 and Uruguay's national shrine of Our Lady of Guadalupe in 2020.
More drives to Fray Marcos
- Nueva Helvecia to Fray Marcos
- Colonia del Sacramento to Fray Marcos
- Carmelo to Fray Marcos
- Paysandú to Fray Marcos
- Rivera to Fray Marcos
- Salto to Fray Marcos
More drives from San Nicolás de los Arroyos
- San Nicolás de los Arroyos to Tigre
- San Nicolás de los Arroyos to Adrogué
- San Nicolás de los Arroyos to Berisso
- San Nicolás de los Arroyos to Magdalena
- San Nicolás de los Arroyos to Chascomús
- San Nicolás de los Arroyos to Cariló
Frequently asked questions
How long is the drive from San Nicolás de los Arroyos to Fray Marcos, Uruguay?
About 8 h 55 min of driving without stops, over 427 miles.
How far is Fray Marcos, Uruguay from San Nicolás de los Arroyos by car?
About 427 miles (687 km) on the Wayro route. Other map services may show a few miles more or less, depending on where they start and end in each city.
Where does the San Nicolás de los Arroyos to Fray Marcos drive cross the border?
At about mile 209, from Argentina into Uruguay, at the Gualeguaychú–Fray Bentos bridge.
What do U.S. citizens need to drive from San Nicolás de los Arroyos into Uruguay?
No visa needed for visits of 90 days or less. Passport: must be valid for 6 months beyond your arrival date. You can drive on your U.S. license. (U.S. State Department, updated August 13, 2026.)
What does the U.S. travel advisory say about the San Nicolás de los Arroyos to Fray Marcos drive?
The U.S. State Department rates Argentina Level 1: Exercise Normal Precautions; Uruguay Level 2: Exercise Increased Caution. Read the full advisory before you go.
Which highways go from San Nicolás de los Arroyos to Fray Marcos?
In order: RN9, RN12, RN14 and RN136. The road-by-road table above shows the route miles for each one.
What are good stops between San Nicolás de los Arroyos and Fray Marcos?
Closest to the road: Cathedral of Mercedes (cathedral, mile 227, 0.8 mi from the route); Museo Departamental de San José (history museum, mile 344, 0.7 mi from the route); Cathedral of Our Lady of Guadalupe (cathedral, mile 378, 0.2 mi from the route). All stops are described above.
How we put this guide together
Wayro calculates the route from OpenStreetMap road data; mile numbers are positions along this route, not highway markers, and "from the route" distances are straight-line, so the real detour depends on access roads. Stops are chosen from parks, natural sites, museums, historic sites and attractions close to the route: at least one strong stop for each stretch of the drive, then the best-known places nearest the road, up to nine in all. Places that are closed, private or not open to visitors are removed. Place descriptions are written by the Wayro team from official park, museum, tourism and government websites and other published sources. Safety levels and entry rules were checked against the U.S. Department of State on October 10, 2026. Conditions change, so check the linked sources before you travel.
Route data © OpenStreetMap contributors.