The main building of the Castle was designed to hold the Institution’s public facilities, such as the library, lecture halls, and museum.

From the beginning, the lower main hall was intended to be used as a public area.

When the space was first finished, it was filled with exhibitions of natural history specimens.

Although no legislation governing it had been passed by Congress, the term “National Museum” was unofficially adopted for the collections exhibited in the Lower Main Hall beginning about 1859.

The original collections eventually grew to fill three additional Smithsonian museums.

With the launching of each new museum and the removal of collections from the building, the use of the Castle’s main hall space was reconsidered.

After the first National Museum (now called the Arts and Industries Building) was opened in 1881, the exhibition space was divided between curatorial and public functions.

The completion of the Natural History Museum in 1911 prompted the hall’s conversion into a library, with related graphic arts displays sharing the space.

The hall was again cleared in the 1960s, when the graphic arts displays were moved to the newly erected National Museum of History and Technology (now the National Museum of American History).

A public information center was then created in the space and a new name, the Great Hall, was adopted.

The information center was refined and updated over the next twenty years with exhibitions emphasizing the origins and development of both the Smithsonian and Washington, D.C.

Foreign dignitaries, heads of state, and cultural figures were received here throughout the 1960s and 1970s.

In the 1980s, the renovated Great Hall became the official home of the Visitor Information and Associates Reception Center and still serves as the gateway to the entire Smithsonian.

In 1992, a gift shop was added the Great Hall’s northeast quadrant, followed in 2003 by a cafeteria occupying one of the former theater spaces.

Its tables and chairs spill out into the Hall's southeast quadrant.

The West Wing and West Range (now known as the Commons and Schermer Hall) were ideal for a gallery of art, as designated in the 1849 plan for the building; however, when the Castle’s west end was completed, the West Wing instead housed the Smithsonian library, and the adjoining range was furnished as a reading room.

It was not until the fire of 1865, after which the Smithsonian's library was transferred to the Library of Congress, that the West Wing and West Range were wholly dedicated to use as exhibition spaces.

These two spaces provided educational exhibitions for more than 100 years.

With the completion of the Museum of History and Technology (now the National Museum of American History) in 1964, the last museum exhibitions remaining in the Castle were removed.

The subsequent renovation in the late 1960s allocated the grand Gothic spaces of the West Wing and West Range for use as communal gathering places for scholars, staff, and visitors.

In the 1970s, the West Wing was designated as a dining room and a lounge reserved for use by scholars as a social center and was renamed the Commons, a term used for the dining halls at English medieval colleges.

For the next 33 years, it was used as a dining hall, until the Commons restaurant closed in 2003.

The West Wing reopened to the public in 2004 with the exhibition, America’s Treasure Chest, featuring refurbished 19th-century display cases filled with artifacts from all the Smithsonian's museums.

While the Commons was used as a dining room, the West Range (Schermer Hall) provided additional dining-room seating and a space for lectures and evening receptions.

When the Commons was converted back into an exhibition hall in 2004, Schermer Hall also received a makeover, and in 2006 the display cases you can see today were installed.

Fun fact: in 1914, repair work to the Star-Spangled Banner was done in the Commons.