Connecticut - Role: Building
| Holabird House |
| Holcomb, Judah, House |
| Holcomb, Nathaniel, III, House |
| Hollister, Homestead, The |
| Hollister, John, House |
| Holmes, Francis H., House |
| Home Woolen Company |
| Hooker, Elizabeth R., House |
| Hooker, Henry, House |
| Hooker, John and Isabella, House |
| Hooker, Sarah Whitman, House |
| Hose and Hook and Ladder Truck Building |
| Hosmer, Daniel, House |
| Hotchkiss, David, House |
| Hotel America |
| Hotel Beach |
| Housatonic Railroad Station |
| House at 1010 Shuttle Meadow Road |
| House at 111 Maple Avenue |
| House at 130 Hayden Station Road |
| House at 130 Mohegan Avenue |
| House at 140 and 144 Retreat Avenue |
| House at 161 Damascus Road |
| House at 29 Flat Rock Road |
| House at 36 Forest Street |
| House at 44 Court Street |
| House at 590 West Street |
| House at 736 Palisado Avenue |
| House at 847 Main Street, North |
| Howd, Eliphalet, House |
| Howd-Linsley House |
| Howe, John I., House |
| Hoyt-Barnum House |
| Hoyt-Burwell-Morse House |
| Hubbard, Nehemiah, House |
| Humphrey, John, House |
| Humphreys, Gen. David, House |
| Hunt, Dr. Chester, Office |
| Huntington, Col. Joshua, House |
| Huntington, Gen. Jedidiah, House |
| Huntington, Gov. Samuel, House |
| Huntington, Samuel, Birthplace |
| Huntington Street Baptist Church |
| Hurd, William, House |
| Hurlbutt Street School |
| Hurley Road Historic District |
| Hurwood Company |
| Hyatt, Thomas, House |
| Hyde-St. John House |
| Hyland-Wildman House |
| Imperial Granum-Joseph Parker Buildings |
| Indian Harbor Yacht Club |
| Isham-Terry House |
| Israel Putnam School |
| Ives-Baldwin House |
| Ives, Charles, House |
| James Pharmacy |
| James Pratt Funeral Service |
| Jerome, William I, House |
| Jillson, William, Stone House |
| Johnson, Alphonso, House |
| Johnson, Franklin, House |
| Johnson, Wilfred X., House |
| Jones, Theophilus, House |
| Judd and Root Building |
| Judson, Capt. David, House |
| June, Lewis, House |
| Keeler Tavern |
| Kellogg, Enos, House |
| Kellogg, Gen. Martin, House |
| Kelsey, Enoch, House |
| Kelsey, Ezekiel, House |
| Kendrick, John, House |
| Keney Tower |
| Kensington Grammar School-Jean E. Hooker High School |
| Killingly High School, Old |
| Kimberly Mansion |
| King, Alexander, House |
| King, George, House |
| King's Field House |
| Knap, John, House |
| Knapp Tavern |
| Knesseth Israel Synagogue |
| Knowlton Memorial Hall |
| Kraus Corset Factory |
| Lakeville Manor |
| Lambert, David, House |
| Lamb Homestead |
| Lathrop, Dr. Daniel, School |
| Lathrop, Dr. Joshua, House |
| Lathrop-Mathewson-Ross House |
| Lattin, Nathan B., Farm |
| Laurel Beach Casino |
| Lawrence, Isaac, House |
| Lay-Pritchett House |
| Lee, Daniel and Mary, House |
| Lee, John Black, House I |
| Leete, Pelatiah, House |
| Lee, Thomas, House |
| Leffingwell Inn |
Data from United States Park Service and Wikidata
