Right answer: un diamante que marca el kilómetro cero
Firstly it is important to explain that the Salón de los pasos perdidos is the name given to a central hall in a building, in which people pass by, in order to go from one room to the other. Generally this room is roofed and spacious, with few furniture and no one is expected to spend more than a few minutes to get through, not to stay there.
Halls with these descriptions exist in several countries of the world (in the venues of their congresses, generally).
Now, in the case of Cuba, inside the Havana Capitol (a building built in 1929 destined to be the headquarter of the two Chambers of Congress of the Republic of Cuba), there is a hall with these characteristics , and has the peculiarity of having at the foot of the Statue of the Republic, a 25 carat diamond (placed under the dome of the Capitol) embedded in the marble floor that marks the zero kilometer as the starting point of all the roads of the island.
