above the present street where it turns from the Via di Porta del Sole
into the Corso Pierluigi. This Porta del Sole[62] was the principal gate
of the town at this time, or perhaps the one most easily defended, for
in 1656, during the plague in Rome, all the other gates were walled up,
and this one alone left open.[63]

The present gates of the city are: one, at the southeast corner, the
Porta del Sole; two, near the southwest corner, where the wall turns up
toward S. Martino, a gate now closed;[64] three, Porta S. Martino, at
the southwest corner of the town; on the west side of the city, none at
all; four, Porta S. Francesco at the northwest corner of the city
proper; five, a gate in the arx wall, now closed,[65] beside the
mediaeval gate, which is just at the head of the depression shown in
plate III, the lowest point in the wall of the citadel; on the east,
Porta S. Cesareo, some distance above the town, six; seven, Porta dei
Cappuccini, which is on the same terrace as Porta S. Francesco; eight,
Portella, the eastern outlet of the Via della Portella; nine, a postern
just below the Portella, and not now in use;[66] ten, Porta delle
Monache or Santa Maria, in front of the church of that name. The most
ancient of these, and the ones which were in the earliest circle of the
cyclopean wall, are five in number: Porta S. Francesco,[67] the gate
into the arx, Porta S. Cesareo,[68] Porta dei Cappuccini, and the
postern at the corner where the early cyclopean cross wall struck the
main wall.

The second wall of the city, which was rather an enlargement of the
first, was cyclopean on the east as far as the present Porta del Sole,
and either scarped cliff or opus quadratum round to Porta S. Martino,
and up to Porta S. Francesco.[69] At the east end of the modern Corso,
there was a gate, made of opus quadratum,[70] as is shown not only by