The size of the Roman foot, or pes, is known from the bronze and stone graduated foot rules that have survived from antiquity; see, for example, Jean-Pierre Adam, Roman Building: Material and Techniques (London: Batsford), pp. 40–41. The standard value of the Roman foot was between 0.294 and 0.296 meters, as compared with 0.3048 meters for the modern foot. However, the foot length employed in Roman buildings across the empire has been shown to vary from 0.24 meters to 0.33 meters. A foot of 0.309 meters for Herod’s Temple was deduced by Rafi Grafman (“Herod’s Foot and Robinson’s Arch,” Israel Exploration Journal [IEJ] 20 [1970], pp. 60–66) from measurements of Robinson’s Arch, and this value is consistent with the dimensions of other features at the Temple Mount, including step heights, as discussed in this article. It is also compatible with a cubit of 0.465 meters, with 3 Roman feet being equivalent to 2 cubits.