The large open part of a Roman house was called the atrium.
This is the colosseum. It is still there today and open to visitors.
Everyone in Roman Society. Large cities had public baths that was open to all.
The Palaestra was the exercise area, often a large open court.
A large rectangular Roman administrative building is called a "basilica." These structures served various functions, including as courts of law and public meeting places, characterized by their long, open interior spaces and often featuring an apse at one or both ends. The design of basilicas influenced later architectural styles, particularly in early Christian churches.
It is usually called a landing.
The ancient Romans called any large open area a campus. An example is the Campus Martius at Rome.
A peristyle is a type of Greek and Roman architechture which resembles a porch/deck with large columns, sometimes in an open area of a building (colonnade).
A forum was the Roman market place or open central area. In Greece called agora.
The open air market to all Greek cities was called Agora and every day life was taking place there. The Roman equivalent was called Forum.
Large open economy.
It is called Montpelier and is now open to the public.
That was our fourth president, James Madison.