The Cabildo was the scene of May Revolution of 1810, which marked the beginning of the construction of Argentina. It is, therefore, an emblematic building. The National Historical Museum of the Cabildo of Buenos Aires and the May Revolution deals with that central theme of Argentine history and proposes a tour of the colonial period and the revolutionary process that ended it.
The Museum combines heritage pieces with contemporary technological resources. Thus, objects of great historical value are exhibited such as a royal banner, the old coat of arms of the city of Buenos Aires, a silver and gold foil that the city of Oruro sent in celebration of the victories over the English invasions, belongings of the members of the First Board, the title of lawyer of Mariano Moreno, the mobile printing press that Manuel Belgrano carried in one of his campaigns, the medal awarded to a revolutionary slave, among others.