The Huguenot Tunnel was closed on Saturday morning after a bus travelling through it caught fire.
Firefighters from Drakenstein municipality and the tunnel’s fire team extinguished the blaze, which is believed to have been caused by an electrical fault.
All passengers were evacuated safely, though one person sustained minor injuries and was taken to hospital, the municipality confirmed.
The Breede Valley Municipality said the scene has been cleared but the tunnel suffered structural damage. It will remain closed until engineers complete a full assessment.
The tunnel is a key link between Paarl and Worcester, carrying traffic along the N1 route between Cape Town and the interior. Motorists have been advised to use alternative routes until it reopens.
