The Porta Nomentana, or what is left of it, is located along the Viale del Policlinico in Rome.
Porta Nomentana Rome
History and description
Though nowadays part of the wall around the British Embassy, the Porta Nomentana used to be a gate in the Aurelian Walls. The Porta Nomentana was closed when Michelangelo was commissioned to build the Porta Pia.
The Porta Nomentana, which was built by the Emperor Adrian in the 3rd century, only had one single arch. To the right of this arch (seen from outside the walls) stood a semicircular tower, which is still there. There used to be another tower on the left, holding the tomb of Quintus Aterius, an orator at Tiberius‘ court. The marble from that tomb was later used to cover the gate itself, while the tower itself was demolished in 1827.
In 1564 Pope Pius IV had an extra gate added to the Porta Nomentana. However, he had it replaced by the Porta Pia as the access road to the Via Nomentana. The still visible brick arch with the papal arms stem from that period.