Built under the rule of Tiberius in the 1st century and reformed until the 3rd century, the Roman wall of Saragossa reached a length of some 3,000 metres and some 120 defensive towers. Two sections have been preserved: the longest, some 80 metres long, at the northwest end of what was the Roman city of Caesaraugusta, next to the Torreón de La Zuda, and another on the northeast side, which now forms part of the Convent of the Holy Sepulchre.

Its layout, studied by Francisco Íñiguez Almech, must have been regular, with a height of about ten metres and a width of four metres. At intervals of between fourteen and sixteen metres there were ultra-semicircular towers, with a diameter of between 8 and 13 metres. The walls of the Roman foundation enclosed and conditioned the urban layout for many centuries, as they were reused by the Visigoths and Muslims.