In Rome he designed the ceremonial entrance to the Castel Sant'Angelo, and made drawings of his restoration, in section and elevation, of the Mausoleum of Hadrian as it had originally appeared. He designed and began the rebuilding of Santa Maria in Traspontina in the Borgo (from 1566, not finished until 1668), where the travertine for its facade was quarried from the Colosseum. He collaborated with Pirro Ligorio at the Casina of Pope Pius IV. Moreover, he supervised the construction, at the expense of the Jewish community, of the walls of the Roman Ghetto.
After 1567 he went to Vienna, where he worked as an engineer and architect for Emperor Maximilian II.
- Römisches Jahrbuch der Bibliotheca Hertziana, vol 35, Ernst Wasmuth Verlag, 2005, p.285.
- Uffizi, acc. no. 646, noted in S. Rowland Pierce, "The Mausoleum of Hadrian and the Pons Aelius", The Journal of Roman Studies 15, (1925:75-103) p. 80, under no. 14.