Soffit
A battlement.
The columns
Barrell vaults
I must admit it's a big question. Architectural features can be found in the domains of aesthetics, construction and functionality. Examples: A column has a constructional purpose: it holds the building A mosaic on a ceiling, voluts and finish of materials contribute to the buildings aesthetics. Hospitals has got a high degree of functionality to make sure it's efficient. The degree to which these three areas are covered in a building is varying in a way that suits the needs. The architectural feature can be any part of a building. Of course a corner of a wall isn't necessarily the most interesting thing to look at, but if it's fitted to the floor in a special way, you could call it an architectural feature.
The major architectural feature of the Colosseum and other Roman buildings was the use of concrete.
The Banaue Rice Terraces in the Philippines are a major historical and architectural feature. They are man-made terraces that were carved into the mountains over 2,000 years ago by the Ifugao people. The terraces are not only functional for rice cultivation but also serve as a stunning example of ancient engineering and sustainable agriculture.
soffit, an architectural feature
Soffit
A battlement.
One major feature are the abs.
The columns
The columns
Barrell vaults
Stephen P. Major has written: 'Architectural woodwork' -- subject(s): Architectural woodwork
a ballcourt
Those letters spell gargoyles, an architectural feature.