Maryland - Area of significance: Architecture
| Berkley Crossroads Historic District |
| Berlin Commercial District |
| Best Endeavor |
| Bethesda Meetinghouse |
| Bethesda Naval Hospital Tower |
| Bethesda Theatre |
| Bethlehem Methodist Episcopal Church |
| Betterton Historic District |
| Beverly |
| Beverly |
| Big Bottom Farm |
| Biggs, William and Catherine, Farm |
| Bingham-Brewer House |
| Bishopton |
| Bloomingdale |
| Bloomsbury |
| B & O Bridge |
| Bohemia Farm |
| Bolton Hill Historic District |
| Bon Air |
| Boonsboro Historic District |
| Borden Mines Superintendent's House |
| Borderside |
| Bostwick |
| Bounds Lott |
| Bowie Railroad Buildings |
| Bowieville |
| Bowling Heights |
| Bowlingly |
| Bowlus Mill House |
| Bowman House |
| Brampton |
| Brandenburg, Henry, House |
| Branton Manor |
| Breakneck Road Historic District |
| Brentwood Farm |
| Brewers Exchange |
| Brewers Hill Historic District |
| Brice House |
| Brick House Farm |
| Brick House on the Pike |
| Brightwood |
| Broad Creek Historic District |
| Brookefield of the Berrys |
| Brookeville Historic District |
| Brookeville Woolen Mill and House |
| Brooklandville House |
| Brooklandwood |
| Broom's Bloom |
| Brown, Alex, Building |
| Brown, Jeremiah, House and Mill Site |
| Brown, Mercer, House |
| Brown, Moses, House |
| Brown's Arcade |
| Brunswick Historic District |
| Bryantown Historic District |
| Buckeystown Historic District |
| Buck House |
| Buckingham House and Industrial School Complex |
| Buena Vista |
| Building at 239 North Gay Street |
| Building at 409 West Baltimore Street |
| Building at 419 West Baltimore Street |
| Building at 423 West Baltimore Street |
| Buildings at 10, 12, 14, and 16 East Chase Street |
| Buildings at 1601-1830 St. Paul Street and 12-20 E. Lafayette Street |
| Bunker Hill |
| Burkittsville |
| Burleigh |
| Burley Manor |
| Burrages End |
| Business and Government Historic District |
| Butchers Hill Historic District |
| Butler House |
| Butler, Wright, House |
| Caldicott |
| Caleb's Discovery |
| Callahan, John, House |
| Calvert Hills Historic District |
| Cambridge Historic District, Wards I and III |
| Camp Greentop Historic District |
| Camp Misty Mount Historic District |
| Canada Hose Company Building |
| Cannonball House |
| Cannon, Burton, House |
| Canton Historic District |
| Canton House |
| Captain's Houses |
| Carderock Springs Historic District |
| Carroll County Almshouse and Farm |
| Carroll Mansion |
| Carrollton Hall |
| Carrollton Manor |
| Carrollton Viaduct |
| Carvill Hall |
| Castle Hall |
| Catalpa Farm |
| Cathedral Hill Historic District |
| Catoctin Furnace Historic District |
| Catoctin Mountain Park |
Data from United States Park Service and Wikidata