It is spacious hall on the first floor of the Palazzo Pubblico where the Grand and General Council (the parliament of San Marino) conducts its sessions. The council has 60 members elected for a five-year term.
Although the building itself was built between 1884 and 1894, for the first time the citizens of San Marino elected an assembly called Council of the LX, which was also known as the Grand and General Council, in the early 13th century.
San Marino was originally led by the Arengo, initially formed from the heads of each family. In the 13th century, power was given to the Grand and General Council. In 1243, the first two Captains Regent were nominated by the Council. As of 2016, this method of nomination is still in use.
Every six months, the council elects two Captains Regent to be the heads of state. The Regents are chosen from opposing parties so that there is a balance of power. They serve a six-month term. The investiture of the Captains Regent takes place on 1 April and 1 October in every year. Once this term is over, citizens have three days in which to file complaints about the Captains' activities. If they warrant it, judicial proceedings against the ex-head(s) of state can be initiated.
The practice of having two heads of state, like Roman consuls, chosen in frequent elections, is derived directly from the customs of the Roman Republic. The Council is equivalent to the Roman Senate; the Captains Regent, to the consuls of ancient Rome. It is thought the inhabitants of the area came together as Roman rule collapsed to form a rudimentary government for their own protection from foreign rule.
During the fascism period, between 1923 and 1943, the Grand and General Council was dissolved and a new legislature called the Prince and Sovereign Council (Italian: Consiglio Principe e Sovrano) was formed, with all its 60 members belonging to the Sammarinese Fascist Party.