Brandbergtunnel, Road tunnel in Zillertal, Austria

Brandbergtunnel is a road tunnel in Tyrol connecting Mayrhofen-Laubichl with Brandberg, giving a direct link between the Zillertal and the Zillergrund. It was built to serve the construction of the Zillergründl dam, which explains its notably steep gradient for a road tunnel. It is about 2.5 kilometres long and carries cars and motorcycles, but not pedestrians or cyclists.

Tauernkraftwerke AG started construction in 1976 to provide access to the Zillergründl dam building site in the Austrian Alps. The project became part of the region's water power development efforts.

The tunnel was built to carry construction traffic to the Zillergründl dam site, and it now gives the villages of Mayrhofen-Laubichl and Brandberg a direct road link across the Ziller valley. Its steep climb, unusual for a road tunnel, is a legacy of that construction purpose.

Drivers can use the tunnel to cross Zillertal without detouring through Mayrhofen town. The route demands attention due to the steep gradient as it climbs through the mountain passage.

The tunnel stands out for its unusually steep gradient compared to typical road tunnels. This technical feature makes it a notable example of mountain construction adapted to extreme Alpine conditions.