Connecticut - Significance region: National
| Allis-Bushnell House |
| Alsop, Richard IV, House |
| Anderson, Leroy, House |
| Armsmear |
| Austin, A. Everett, House |
| Baldwin, Caleb, Tavern |
| Ball and Roller Bearing Company |
| Barnard, Henry, House |
| Barnum Museum |
| Basset, Daniel, House |
| BERKSHIRE NO. 7 |
| Bigelow-Hartford Carpet Mills |
| Birdcraft Sanctuary |
| Black Rock Gardens Historic District |
| Bowen, Henry C., House |
| Branford House |
| Bush-Holley House |
| Buttolph-Williams House |
| Camps Nos. 10 and 41 of Rochambeau's Army |
| Cedar Hill Cemetery |
| CHARLES W. MORGAN |
| Cheney Brothers Historic District |
| Chittenden, Russell Henry, House |
| Christ Church New Haven |
| CHRISTEEN (oyster sloop) |
| Church of the Good Shepherd and Parish House |
| Collinsville Historic District |
| Colt Industrial District |
| Connecticut Agricultural Experiment Station |
| Connecticut General Life Insurance Company Headquarters |
| Connecticut Hall, Yale University |
| Connecticut State Capitol |
| Connecticut Statehouse |
| Cos Cob Power Station |
| Crandall, Prudence, House |
| Cream Hill Agricultural School |
| Dana, James Dwight, House |
| Deane, Silas, House |
| DORIS (Sailing yacht) |
| Dorrance Inn |
| Durisol House |
| Ellsworth, Oliver, Homestead |
| ELMER S. DAILEY |
| EMMA C. BERRY (Fishing Sloop) |
| Eno, Amos, House |
| Eolia-Harkness Estate |
| Fifth Camp of Rochambeau's Infantry |
| First Church of Christ |
| Fort Griswold |
| Fort Shantok |
| Fort Trumbull |
| Forty-Seventh Camp of Rochambeau's Army |
| Fourth Camp of Rochambeau's Army |
| Fuller Brush Company Factory Complex |
| Gateway Village Historic District |
| Glebe House |
| Griswold, Florence, House and Museum |
| Grove Street Cemetery |
| Guilford Historic Town Center |
| Hale, Nathan, Homestead |
| Hatheway House |
| Hill-Stead |
| Hodgson, Richard and Geraldine, House |
| Hooker, Sarah Whitman, House |
| Howe, John I., House |
| Huntington, Samuel, Birthplace |
| Ives, Charles, House |
| Johnson, Philip, Glass House |
| Kimberly Mansion |
| L. A. DUNTON |
| Lake Compounce Carousel |
| Lakeview Village Historic District |
| Lebanon Green Historic District |
| Lime Rock Park Race Track |
| Litchfield Historic District |
| Litchfield Historic District |
| Little Pootatuck Brook Archeological Site |
| Lockwood-Mathews Mansion |
| March Route of Rochambeau's Army: Bailey Road |
| March Route of Rochambeau's Army: Manship Road-Barstow Road |
| March Route of Rochambeau's Army: Reservoir Road |
| March Route Rochambeau's Army-Hutchinson Road |
| Marsh, Othniel C., House |
| Mashantucket Pequot Reservation |
| Mather, Stephen Tyng, House |
| Mendel, Lafayette B., House |
| Merrill, James, House |
| Merritt Parkway |
| Middle Haddam Historic District |
| Monte Cristo Cottage |
| Morley, Edward W., House |
| Mory's |
| Mystic Bridge Historic District |
| New Haven City Hall |
| New Haven County Courthouse |
| New Haven Green Historic District |
| Norton, Charles H., House |
| Noyes House |
| Old Mine Park Archeological Site |
| Old Newgate Prison |
Data from United States Park Service and Wikidata
