RN5 Tunnels: Driving the Narrow Peter Both and Gueule Rouge Tunnels in Réunion
The Route Nationale 5 (RN5) connects Saint-Louis and Cilaos on the French island of Réunion, in the Indian Ocean. This asphalted mountain road features two narrow single-lane rock tunnels carved into the volcanic cliffs, where two cars cannot pass each other at the same time.
| Road facts: RN5 Tunnels (Peter Both & Gueule Rouge) | |
|---|---|
| Location | Route Nationale 5, Réunion Island |
| Tunnel de Peter Both Length | 166.51 m (546.28 ft) — Built in 1960 |
| Tunnel de Gueule Rouge Length | 114.54 m (375.78 ft) — Built in 1938 |
| Maximum Height | 3.0 meters (9.8 ft) for both tunnels |
| Surface | Fully paved asphalt |
Why is it called Tunnel de Peter Both?
Built in 1960, Tunnel de Peter Both is 166.51 meters long and 3 meters high. The structure gets its name from Piton Peter Both, the nearby volcanic rock peak named after Pieter Both, the first Governor-General of the Dutch East Indies. The asphalt track inside is narrow, forcing drivers to stop at the entrance if another vehicle is already inside the mountain.
Why is it called Tunnel de Gueule Rouge?
Carved into the rock in 1938, Tunnel de Gueule Rouge is 114.54 meters long and 3 meters high. The name Gueule Rouge (Red Mouth) comes from the red color of the local volcanic earth and rocks, which contain high amounts of iron oxide. The unlit interior follows a tight curve that blocks the view of oncoming cars.
What are the driving restrictions in the RN5 tunnels?
Both rock tunnels have a strict headroom limit of 3.0 meters, which blocks high-clearance camper vans, trucks, and heavy vehicles from using this section of the RN5. Because the unlit channels lack a center line or side shoulders, cars must wait for oncoming headlights to clear the narrow vaults before driving into the dark openings.