The deepest underground tunnel in Malaysia is the SMART Tunnel, which is located about 20 meters below sea level. It is the first tunnel in the world to carry vehicles and also rainwater when needed. But the depth of the SMART Tunnel cannot be compared to the Rogaland Fastforbindelse (Rogfast) project currently being built in Norway.
Rogfast, when completed, will be the deepest underground tunnel for vehicles in the world, located 390m below sea level. It will also be the world's longest underground tunnel with a length of 27 kilometers.
Two tunnels, each with two lanes, were built and, uniquely, in the middle of Rogfast, two roundabouts were built at a depth of 260 meters to allow users to choose to go to three different destinations.
The project was built to connect Randaberg, Bokn and Kvitsøy, which are currently separated by the ocean. Residents who have been relying on ferry services will shorten their journey by 40 minutes.
The project was originally started in 2018 but was delayed due to lack of funding. It was supposed to open by 2025 but has now been delayed to 2033. The total cost of the project is estimated at NOK 25 billion (~RM 10.25 billion).
