Bab Saadoun is one of the old gates of Tunis, marking the western side of the historic city. The original medieval gate had a single arch; the three-arched form seen today dates from an 1881 rebuilding that made room for heavier traffic and commerce.
It is a quick architectural stop rather than a destination by itself. Use it as a marker while exploring the northern and western edges of the medina, where the old city begins to loosen into busier modern streets.