Significant parts of the city walls of Piran remain well-preserved. Piran's three walls were built in response to the city's expansion. The first wall was built in the 7th century, separating the town into four streets. The first wall can be seen in the old part of the town. The wall was moved south-west when new streets were built. The fortification wall, which was built along the southern coast of the town, hasn't changed much since it was first built.
In the final phases of expansion between 1470 and 1538, the second fortification wall was built to protect the peninsula during construction. It protected the MarÄana quarter. The biggest part was built when the use of gunpowder became frequent.
The third wall is almost completely intact. Its northern part is accessible while the southern wall's floors and stairs are missing or are under reconstruction. Between them a gap opened where the wall collapsed. A small portion of the third wall is next to the rectory, facing north. A tower viewer is located in one of the towers.Seven city entrances or gates remain preserved.
References:The Basilica of Santa Maria in Trastevere is one of the oldest churches of Rome. The basic floor plan and wall structure of the church date back to the 340s, and much of the structure to 1140-43. The first sanctuary was built in 221 and 227 by Pope Callixtus I and later completed by Pope Julius I.
The inscription on the episcopal throne states that this is the first church in Rome dedicated to Mary, mother of Jesus, although some claim that privilege belongs to the Basilica di Santa Maria Maggiore. A Christian house-church was founded here about 220 by Pope Saint Callixtus I (217-222) on the site of the Taberna meritoria, a refuge for retired soldiers. The area was made available for Christian use by Emperor Alexander Severus when he settled a dispute between the Christians and tavern-keepers.
The church underwent two restorations in the fifth and eighth centuries and in 1140-43 it was re-erected on its old foundations under Pope Innocent II.