unbuilt
An unrealized structure design for which construction is no longer expected or was never reasonably expected.
Any unrealized building design is classified as unbuilt, whether it was intended to be realized or not. In order to be covered even unbuilt structures must have minimum design specifications (including physical outline and exact location).
Many structures assume this status after their plans are canceled. Others (such as visions) are classified as unbuilt from the moment their designs are released.
An active planned project has a reasonable likelihood of construction. The unbuilt cases instead include an abandoned serious proposal and a design released without that expectation.
