Dragon's teeth are pyramidal anti-tank obstacles of reinforced concrete first used during the Second World War to impede the movement of tanks and mechanised infantry. The idea was to slow down and channel tanks into killing zones where they could easily be disposed of by anti-tank weapons.
They were employed extensively, particularly on the Siegfried Line.[1][2][3]
This section of the Siegfried Line sat in the middle of the Hardt Mountains, where the landscape was dotted with pillboxes and dragon teeth tank obstacles.
it was late afternoon on 18 Feb when [we] passed through the Siegfried Line dragons teeth
Human-made obstacles such as the "dragon teeth" were integrated carefully into the defense system of the line.