Supporting evidence is drawn not only from the instruments of time in the form of the roofed spherical
sundial, but also from other Imperial monuments, notably Nero’s Domus Aurea and Augustus’s
complex of structures on the Campus Martius – his Ara Pacis, the ‘Horologium Augusti’, and his
Mausoleum. Hadrian’s Mausoleum and potentially part of his Villa at Tivoli are drawn into this
argument as correlatives. Ultimately, it is proposed that sun and time were linked architecturally into
cosmological signposts for those Romans who could read such things.