- O'Riley, Addie1
- O'Riley, Kathleen1
- O'Riley, Mamie1
- Office equipment and supplies1
- Oil mills5
- Oliver Motor Company (Columbia, S.C.)1
- Olympia Cotton Mills (Columbia, S.C.)5
- Olympia High School (Columbia, S.C.)2
- Organ (Musical instrument)1
- Owens Field Municipal Airport (Columbia, S.C.)9
- Owens, Frank Capers, 1898-19831
- Owens, Lawrence Beacham, 1869-19411
- Palmetto Gay and Lesbian Association2
- Panoramic views3
- Parades23
- Parking lots1
- Parks15
- Parsonages1
- Pen Branch Methodist Church (Woodford, S.C.)1
- Pharmacists1