[3] An idea for a tunnel through the Du Toitskloof Mountains was conceived in the 1930s but was put on hold due to the outbreak of World War II.

[4] A 1983 economic impact assessment estimated that the construction of the tunnel would contribute R200 million to the economy of the Western Cape by 1988.

[1] The tunnel was designed by South African VKE and Swiss Electrowatt, Zurich consulting engineers.

Plans are underway to open a second unfinished tunnel, the "northern bore", to carry eastbound traffic.

The toll as proclaimed on 1 March 2019[11] was (in South African Rand): The tunnel has 13 video cameras that feed into an automatic incident detection system, which can sound alarm devices for any of the following conditions: