Running along the southern wall was a stepped walkway, 6.4 m (21 ft) wide, with stores built under it. In front of this was a large plaza, with steps leading to the two gates in this wall. 

   The southern wall of Hurdus's expansion of Har Habayis, is 281 m (922 ft) long. This wall is approximately at a ninety-degree angle to the Western Wall. This wall is entirely from Hurdus's time, as can be seen from the style of the stones. This wall extends from Nachal Kidron in the east, to the Tyropoeon valley in the west; the western part of the wall is actually built over the valley. In this wall are two gates, the double gate and the triple gate, which we will Imy"h discus in future posts. 

    By the southwest corner of the Har Habayis, next to the gate above Robinson's arch, were chambers. On the roof of these chambers, a Kohen used to blow a trumpet every Friday, to signal that Shabbos is coming. During Binyamin Mazar's excavations, a stone was found, that mentioned this "Beis Hatekiah"-place of trumpeting. This corner is very suitable for this task, as it was high up, and faced the whole city, so it was easily heard. It was also right next to the main road of Yerushalayim, so everyone who was there knew it was time to close up shop and get ready for Shabbos. 

   Running under the main street of Yerushalayim was a large drainage channel, partly cut into the rock. This channel went from the north of the city to the south, passing on the west of the Shiloach pool and exiting the city there. This drain was originally built at some point before Hurdus's time and was roofed with flat stone slabs. When Hurdus expanded the Har Habayis, the walls cut this drain, so a "by-pass” (with a vaulted roof) was made to connect the two severed sections of the drain. This "bypass" cut through several underground caves and cisterns in the area. A network of channels brought the water from the street and nearby buildings to this drainage channel. One paving stone by the western curb of the street, (right by the southwest corner of Har Habayis,) has five slots in it, for the water to go down to these channels, and from there to the main drainage channel. When the Romans destroyed Yerushalayim, some Yidden tried hiding in this drainage channel, but the romans searched for them and found them, and killed them. (Josephus, Wars 6:9:4 [6:429]).