At the foot of the western retaining wall of the Temple Mount (the modern Western Wall) lay the main commercial street of the city. At the southern part of the street stood Robinson's Arch which bore a large staircase leading from street level to the Royal Stoa.[50] In the southern wall of the mount stood the Huldah Gates, the main entrance to the sacred compound.[51] To their south extended an area of ritual baths serving the pilgrims ascending the mount, and a street leading down to the City of David and the Pool of Siloam. West of the compound lay the deep channel of the Tyropoeon, and beyond it the Upper City, residence of the priests and the affluent.