As people concerned with issues of historic preservation, we tend to think about historic sites and the built environment as they exist today. On a lower order we tend to think of structures that have succumbed to a wrecking ball or fire, yet that may also be fresh in our collective memory. Sioux City residents should be proud of the historically significant places that remain. We should also think of what has been lost, both from the city's earliest history to the most recent destruction. What may escape the thoughts of many individuals, however, are the places and structures that were never built. They were planned but never fulfilled. This incompletion took many forms, perhaps an undeveloped tract of Loess bluff, or a building without originally designed architectural details. In the most extreme cases the structures were never started. Though this article will note several such examples of incompletion, it will focus on three unbuilt structures.