From the designation of individual sections of the Dam as "twergasse versus castrum" (cross-lane toward the castle, 1357) and "twergasse versus valvam" (cross-lane toward the gate, 1377/78), it is clear that the gate already existed before 1378.

In the ground-rent registers of the 15th century, it is usually referred to by the neighboring Holy Spirit Hospital as "dat hillige geist dor by dem huse" (the Holy Spirit gate by the house), because it was the Main Town gate that carried the principal traffic between the city and the house of the Teutonic Order. The Order's gate on this side was located opposite today's Schlossgasse (Castle Lane).

Later the designation "hilliges geist dor by dem huse" was shortened -- especially since it could easily be confused with the two other Holy Spirit Gates on Heilig-Geist-Gasse -- and so the abbreviated name "Haustor" (House Gate) came into use.

Today's street Am Haustor occupies the site of the former gate with its ditch, as well as the space inside the gate, which has been listed in the hereditary registers as "nach dem Haustor" (by the House Gate) since 1415. In 1416, the expression "bey dem ketzerhagen versus valvam" also appears, though it was never used again afterward. The name Ketzerhagen occurs only this once, but there was an entire Ketterhager Gasse (Ketterhagen Lane) in the suburb.

History