It appears that Seomun (West gate) was part of the original fortress and it was restored in 1799, and renamed "Right Side Gate" since it was on the right when facing south from the secondary palace. In 1637, King Injo and the Crown Prince went through this gate to surrender to the Manchus. The slope on the west side of the fortress was too steep for provisions to come through, but those were easily sent through from Gwangnaru or Songpanaru ferry landings.