San Marino Historic Centre and Mount Titano covers 55 ha, including Mount Titano and the historic centre of the city which dates back to the foundation of the republic as a city-state in the 13th century. San Marino is inscribed as a testimony to the continuity of a free republic since the Middle Ages. The inscribed city centre includes fortification towers, walls, gates and bastions, as well as a neo-classical basilica of the 19th century, 14th and 16th century convents, and the Palazzo Publico of the 19th century, as well as the 18th century Titano Theatre. The property represents an historical centre still inhabited and preserving all its institutional functions. Thanks to its position on top of Mount Titano, it was not affected by the urban transformations that have occurred from the advent of the industrial era to today.
Legend tells that the first community was formed here during the late Roman Empire by Saint Marino. The first document regarding the city dates from the beginning of the 6th century and is about a small monastery at the top of Mount Titano. In 885 A.D. there was a lay community, and around 951 A.D. the first parish was formed. There are no visible remains of this period.
In the mid-13th century San Marino had its own legal authority and a first document testifying its independence is dated 1296. Statutes in 1295-1302 mention bodies and institutions which are still maintained in the political system today. By this time the basic structure of the nucleus of the city was already in place: in the southwest ends the First Tower (Rocca or Guaita) at the top of the mountain, then a small area surrounded by the first city wall, and further north the church and a built-up area to the west of this. The separate area of Borgo Maggiore at the foot of the Mount Titano had also started to develop.
Later in the 13th century and in the 14th century a second city wall was built around a much larger area, including the church and the built-up quarter to the north. Parts of this wall still exist, though heavily restored. This period also saw the construction of the two other defensive towers further south on the edge of Mount Titano - the Second Tower (Cesta or Fratta) and the Third Tower (Montale) - as well as the walls to the Fratta Tower. Outside the city wall, the important complex of the Saint Francis' Convent was built in the 1360s, with the oldest existing church in the republic.
Around the mid-15th century, the third circle of defensive walls with three new gates was built. This meant quite an enlargement to the west and today marks the border of the historic centre. The walls were reinforced in the 16th century, and two bastions were built in 1549 and 1559. In 1463 San Marino obtained several territories previously under the control of Rimini and since then the borders of the Republic have remained unchanged.
In the 16th century the Convent of the Capuchin Fathers was built outside the walls to the south, and along the street of Contrada Omerelli, the Convent of Saint Chiara and the majority of the palaces of the most important noble families. This shows the growing importance and wealth of the nobility in this period.
An engraving of 1663 and a cadastral map of 1884 show the basic structure of the streets and some scattered buildings along these in the area west of the walls. However, this area was mainly built out in the 20th century and then extended to the south.
The two major additions of the 19th century are the neoclassical basilica (begun in 1825) replacing the ancient church, and the new Palazzo Pubblico (1884-1894) in a neo-gothic style. This shows the reorganization and modernization of the State, but still resting on the medieval traditions, following the recognition of its sovereignty and liberty by the Kingdom of Italy in 1862. A first general census was held in 1865.
In 1916 a Parliamentary Commission for the Conservation of Antiquities and Art Objects was established, and in 1919 a law for the protection of monuments was passed. The same year the Cesta Tower collapsed. Subsequently the Sammarinese engineer Gino Zani published an extensive report on the restoration of the fortifications, carried out a study based on archival documents and published a book showing the presumed original form of the buildings.
In 1925-1940 Zani restored the three towers and the walls as well as many buildings, among those the façade of Saint Francis' Church, the Titano Theatre, and some palaces. He also realized the Piazza Sant'Agata, an extension of the Hospital of the Misericordia and the new Via Donna Felicissima. In 1935 he produced a planning scheme for the entire historic centre, but this was only partly implemented. A building in modern style is the Cassa de Risparmio bank.
In 1935 Zani also drafted a town planning scheme for the extension of the south-eastern areas outside the city wall (in the buffer zone) with a new entry to the historic centre. In the second half of the 20th century the number of tourists drastically increased and different structures were built to accommodate this, such as the cableway Borgo Maggiore-San Marino, and parking places around the city. A strong commercial character has been established and a great many shop windows opened. New approaching roads on high retaining walls have been constructed and in the areas outside the historic centre some new buildings by famous architects have been built.
The conservation history therefore began with the Commission for the Conservation of Monuments, Antiquities and Art Objects in 1916 and the legislation in 1919. It was characterized by historical restorations up until the Second World War and a strong wish to strengthen the medieval character of the city. Today the historic centre is continuously undergoing restoration activities.