Massachusetts - Significance region: Local
| Old Colony Iron Works-Nesmasket Mills Complex |
| Old Colony Railroad Station |
| Old Common Burial Ground |
| Old County Courthouse |
| Old Curtisville Historic District |
| Old Douglas Center Historic District |
| Old Higgins Farm Windmill |
| Old Hose House |
| Old Indian Meeting House |
| Old Lynn High School |
| Old Medford High School |
| Old Mill |
| Old Mill Site Historic District |
| Old North Cemetery |
| Old Post Office Building |
| Old Post Office Building |
| Old Public Library |
| Old Settlers' Burying Ground |
| Old Shipbuilder's Historic District |
| Old Ship Street Historic District |
| Old South Union Church |
| Old Stone Church |
| Old Town Bridge |
| Old Town Center Historic District |
| Old Town Farm |
| Old Town Hall |
| Old Town Hall |
| Old Town Hall |
| Old Town Hall Historic District |
| Old Town Historic District |
| Old Village Historic District |
| Old Weir Stove Company |
| Oliver House |
| Olmsted-Hixon-Albion Block |
| Olmsted Subdivision Historic District |
| Olney Cook Artisan Shop |
| Orange Armory |
| Orange Center Historic District |
| Original Congregational Church of Wrentham |
| Orne, Sarah, House |
| Orvis Road Historic District |
| Osgood Bradley Building |
| Osgood Hill |
| O'Shea Building |
| Osterville Baptist Church |
| Otis Center Historic District |
| Otis Company Mill No. 1 |
| Otis-Wyman House |
| Our Lady of Good Voyage Church |
| Our Mother of Sorrows Monastery and Retreat Center |
| Outing Park Historic District |
| Oxford-Crown Historic District |
| Oxford Main Street Historic District |
| Oxford School |
| Oxford, The |
| Packard, Moses, House |
| Padanaram Village Historic District |
| Paddock Farm |
| Page, Nathaniel, House |
| Page, Thomas D., House |
| Paine Furniture Building |
| Paine Hollow Road South Historic District |
| Paine, Timothy, House |
| Palmer Memorial Hall |
| Palmer School |
| Pan Burying Ground |
| Pan Historic District |
| Paragon Park Carousel |
| Parker-Burnett House |
| Parker, Capt. Nathaniel, Red House |
| Parker, Edmund, Jr., House |
| Parker, Harrison, Sr., House |
| Parker House |
| Parker House |
| Parker House |
| Parker House |
| Parker, James, House |
| Parker, Joseph, House |
| Parker, Samuel, House |
| Parker, Stillman, House |
| Parker Tavern |
| Parker Village Historic District |
| Parker, William, House |
| Parkhill Mill |
| Park Lodge |
| Parkman Tavern |
| Park Square Historic District |
| Park Street Firehouse |
| Park Street Railroad Station |
| Parsons, Shepherd and Damon, Houses Historic District |
| Partridge, Jabez, Homestead |
| Patton and Loomis Block |
| Patton Building |
| Paull, Alfred, House |
| Paul's Bridge |
| Pawtucket Congregational Church |
| Peabody Central Fire Station |
| Peabody City Hall |
| Peabody Civic Center Historic District |
| Peabody Institute |
Data from United States Park Service and Wikidata
