There are many ways an airship can land. They can be moored to a tower, towed inside a hangar, or land conventionally on the ground using inflatable landing skids. The St. Paul, however, uses the Air Cushion Landing System (ACLS).
The ACLS is essentially a series of hovercraft feet that allow the St. Paul to land on any flat surface, including water. This eliminates the need for extensive infrastructure development (i.e. the construction of airports). This is one of the massive cost benefits of this type of aircraft.
In addition, one the aircraft has landed, the airflow to the ACLS can be reversed, creating suction instead of lift to keep the airship firmly rooted to the ground during loading and unloading procedures. It also allows the St. Paul to taxi forward and backward, and even sliding the enire craft sideways on the ground.