Iowa - Criteria: C (architecture/engineering)
| Wild, Daniel and Margaret, House |
| Wildwood Park Historic District |
| Wilkinson, Thomas C., House |
| Willard, Leroy R., House |
| WILLIAM M. BLACK (dredge) |
| Williges Building |
| Willow-Bluff-3rd Street Historic District |
| Wilson, Anson, House |
| Wilson, Asa, House |
| Wilson Buildings |
| Wilson District #7 School |
| Wilson, Paton and Hannah, House |
| Wilson, Seth and Elizabeth, House |
| Wilton Candy Kitchen |
| Wilton Commercial Historic District |
| Windrem House |
| Winnebago County Courthouse |
| Winnebago River Bridge |
| Winterset Courthouse Square Commercial Historic District |
| Wishard, Henry, House |
| Wolf, Charles, House |
| Wolff, Philip A., House and Carriage House |
| Wolf, Mier, House |
| Wolters Filling Station |
| Woodbine Normal and Grade School |
| Woodbine Public Library |
| Woodbine Savings Bank |
| Woodbury County Courthouse |
| Wood, Herman, Round Barn |
| Woodland Place Historic District |
| Woodlawn Cemetery Gates and Shelter |
| Woodlawn Historic District |
| Woods, Oscar C., House |
| Wood, William Kennison, House |
| Worley, Philip, House |
| Worth County Courthouse |
| W. R. C. Hall |
| Wright County Courthouse |
| Wupperman Block/I.O.O.F. Hall |
| Yale High School Gymnasium |
| Yelland, Curtis, House |
| Yellow Smoke Park Bridge |
| Y.M.C.A. Building |
| YMCA Building |
| Young, Alexander, Cabin |
| Youngblood, Tessa, House |
| Youngerman Block |
| Young, John W., Round Barn |
| Youngville Cafe |
| Zalesky, Frank E. and Katie (Cherveny), House |
| Ziepprecht Block |
| Zitterell, William J. and Hattie J., House |
| Zuhn Building |
| Zwemer Hall, Northwestern College |
Data from United States Park Service and Wikidata
