Maine - Area of significance: Architecture
| Colcord Farmstead |
| Cold Spring Farm |
| Cole Block |
| College Block-Lisbon Block |
| Colonial Apartments |
| Colonial Inn |
| Colonial Theater |
| Columbia House |
| Conant-Sawyer Cottage |
| Concord Haven |
| Congregational Church of Edgecomb |
| Congregational Church of Medway |
| Connor-Bovie House |
| Connors House |
| Conway House |
| Cony, Gov. Samuel, House |
| Cony High School |
| Coombs, Viola, House |
| Coplin Plantation Schoolhouse |
| CORA F. CRESSEY |
| Corinth Town Hall and Corinthian Lodge #59, I.O.O.F. |
| Cornish House |
| Cottage on King's Row |
| Cotton-Smith House |
| Cottrill, Matthew, House |
| Cousins Island Chapel |
| Cover Farm |
| Crooker, W. D., House |
| Crosby Lodge |
| Crosby Street Historic District |
| Cuckolds Light Station |
| Cumberland Mills Historic District |
| Cumston Hall |
| Curtis, John B., Free Public Library |
| Cushman, Abial, Store |
| Cushman, Charles L., House |
| Cushnoc (ME 021.02) |
| Cutler Memorial Library |
| Daigle, Jean-Baptiste, House |
| Dalton, Benjamin and Abigail, House |
| Damariscotta Baptist Church |
| Damariscove Lifesaving Station |
| Davis, Dalton Holmes, Memorial Library |
| Davis, John, House |
| Day, Holman, House |
| Days Ferry Historic District |
| Deacon Hutchins House |
| Deering, J. G., House |
| Deering Memorial United Methodist Church |
| Deering Street Historic District |
| Deertrees Theatre |
| Dennett Garrison |
| Dennysville Historic District |
| Dexter Grist Mill |
| Dexter Universalist Church |
| Dingley, Frank L., House |
| District #5 School House |
| District No. 5 School |
| Division No. 9 School |
| Dix Family Stable |
| Dixmont Corner Church |
| Dominican Block |
| Dorfield Farm |
| Doubling Point Light Station |
| Doughty Block |
| Douglas, C. F., House |
| Dover-Foxcroft Commercial Historic District |
| Dreamhome |
| Dresden Brick School House |
| Drexel Estate |
| Dry Mills School |
| Duck Cove School |
| Dudley Block |
| Dunlap, John, House |
| Dunning, Deacon Andrew, House |
| Dunstan Methodist Episcopal Church |
| Dutton-Small House |
| Dyer-Hutchinson Farm |
| Dyer, Isaac E., Estate |
| Dyer, Nathaniel, House |
| Early Post Office |
| East Blue Hill Library |
| Eastbrook Baptist Church and Eastbrook Town House |
| East Harpswell Free Will Baptist Church |
| East Machias Historic District |
| East Main Street Historic District |
| Eastman Hill Rural Historic District |
| Eastport Historic District |
| East Raymond Union Chapel |
| Eaton House |
| Eaton School |
| Edgecliff |
| Eegonos |
| Egg Rock Light Station |
| Eighth Maine Regiment Memorial |
| Elden's Store |
| Elder Grey Meetinghouse |
| Ellis, Dr. J. W., House |
| Ellsworth City Hall |
| Ellsworth Congregational Church |
Data from United States Park Service and Wikidata
