The Młyńska Gate enclosed the town from the direction of Gdańsk and Smołdzin. Similarly to the Holsten Gate, this structure was built in two stages – first, in the period from 1325 to 1329, the ground floor with an ogival passageway was erected, then, around 1365-1370 the upper floors were added. It was crowned with ornamental tops with pinnacles. During the warfare in March 1945 the Gate was largely destroyed – it lost its floors, roof and tops. After the war in 1951, it was provided with an emergency repair in the form of a hipped tented roof. A general repair and adaptation were carried out in 1980.
The southern façade of the Młyńska Gate adjoins a short section of the defensive town wall. This construction fragment is the oldest preserved in Słupsk and measures 8m in height. Currently, it hosts the restoration workroom of the Museum of Central Pomerania.