<p>The submarine has an upper deck (8) arranged above a pressure body (2) and spaced from the pressure body, where the upper deck is formed by an outer lining (4) arranged in an upper area of the pressure body. A step-like unit for ascending and descending to and from the upper deck is arranged in the outer lining in a range between the pressure body and the upper deck. Multiple recesses (12) are formed at a region of the outer lining leading from the pressure body to the upper deck and arranged one above the other. The recesses are arranged in a vertical row with spacing.</p>
