Never could I have guessed that one of the barrels pointing out from this bunker actually belonged to a tank.
Upon closer inspection I found a complete T-34/85 embedded in the bunker. This bunker has been reconstructed as part of the bunker museum at the Würzenpass, Austria.
In 1955, as part of an aid package, Austria received some 19 battle worn T-34/85 tanks from the Soviet Union. Because these tanks had lost their worth in tank-to-tank combat by then, they were all used as part of static defenses. At strategic points, complete tanks were verbunkert (e.g. put in a bunker). This specific tank served as a defense near Mauthausen. It was broken out of its original bunker in 2006 when it was taken to the museum where it was again put in a bunker.
At the museum’s premises there is also an example where only the turret was used on a pillbox.