How does the European mole build its fortress mound?

The European mole (Talpa europaea) constructs its massive fortress mound by excavating complex systems of galleries, which include specialized storage and nesting chambers.1

To build these structures, the mole braces its body within a tunnel to shear soil from the tunnel face using its powerful forelimbs. It then turns around to push the loose soil through the tunnel and onto the surface, creating a mound. A large fortress mound can consist of up to 750 kg (1,650 pounds) of soil.1