Hanoi Pilot light metro line project - section Nhon-Hanoi railway station

The First Ride Beneath the Lakes of Hanoi

The first underground railway line in the history of the Vietnamese capital, the country’s most populous city. The project was created to promote sustainable economic development in Hanoi, to reduce traffic and greenhouse gas emissions.


Situated in Northern Vietnam, Hanoi was built on alluvial terrains and is known as “The City of Lakes” for the presence of numerous bodies of water. Over the past 30 years the population has exploded to over 8 million inhabitants, most using their own private vehicles. The Ministry of Transportation gave the green light to build the first metro system to reduce the use of private vehicles and increase the livability of the urban environment. An ambitious project to improve economic development in the city: a new public network consisting of 8 metro lines, to be completed by 2050 for 200,000 passengers a day.  

The lot in which Ghella is involved is financed entirely by the Asian Development Bank (ADB). The Pilot Light Metro Line 3, also known as the Văn Mieu Line (Temple of Literature Line), will see the highest use by residents and commuters. The reduction in traffic and greenhouse gas emissions will improve air quality, health, and safety for the entire community.

The project involves the boring of two twin tunnels by two special boring machines: Earth Pressure Balance (EPB) TBMs, boring machines capable of tunneling through highly urbanized areas, and avoiding collapses on the surface above. The construction site thus becomes a part of the city, perfectly integrated and functional, and fully respecting the urban context and life of the city’s inhabitants.

A Few Numbers

The Pilot Light Metro Line 3 is the first underground line in the Vietnamese capital. It runs for 12.5 km from Nhon – in the Tay Tuu quarter, the western district of Nam Tu Liem - to Hanoi Station. The line runs along 8.5 km of elevated track and 4 km of underground track and includes the construction of four stations: Kim Ma Station, Cat Linh Station, Van Mieuh Station and Hanoi Station. Their excavation, already complete, was propaedeutic to the phase of mechanical boring, which began in early 2021.

The Earth Pressure Balance (EPB) TBMs working beneath Hanoi are 6.60 meters in diameter and bore through the rock with a cutting head fitted with cutting discs. They remove material as they bore and the immediately secure tube by placing prefabricated concrete segments.

There are more than 400 workers and technicians involved in the project, for the most part local staff. Another positive aspect: Ghella will transfer its engineering know-how and techniques directly to local resources to guarantee the highest international standards.