Feature Name | Class | Elev. meters | County | Latitude DMS | Longitude DMS |
| River Ridge Estates | Populated Place | 42 | Prince George's | 38 47 11 N | 077 00 10 W |
| River Road Spring | Spring | 58 | Montgomery | 38 59 46 N | 077 09 58 W |
| River Springs | Populated Place | 3 | St. Mary's | 38 14 46 N | 076 46 39 W |
| River Valley Ranch | Locale | 237 | Carroll | 39 42 03 N | 076 48 37 W |
| River View | Locale | 3 | St. Mary's | 38 15 45 N | 076 43 53 W |
| River View | Populated Place | 9 | Calvert | 38 19 31 N | 076 25 44 W |
| River View Cemetery | Cemetery | 126 | Washington | 39 35 52 N | 077 49 30 W |
| River View Hill | Summit | 667 | Garrett | 39 37 34 N | 079 26 00 W |
| River Wood Hills | Populated Place | 212 | Carroll | 39 22 46 N | 077 04 54 W |
| Riverdale | Populated Place | 8 | Anne Arundel | 39 05 57 N | 076 32 09 W |
| Riverdale Baptist Church | Church | 32 | Prince George's | 38 52 25 N | 076 47 33 W |
| Riverdale Elementary School | School | 9 | Prince George's | 38 57 40 N | 076 55 44 W |
| Riverdale Forest | Populated Place | 13 | Anne Arundel | 39 05 55 N | 076 32 44 W |
| Riverdale Gardens | Populated Place | 22 | Prince George's | 38 58 07 N | 076 54 48 W |
| Riverdale Heights | Populated Place | 28 | Prince George's | 38 57 50 N | 076 54 54 W |
| Riverdale Heights Volunteer Fire Department Company 13 | Building | | Prince George's | 39 36 33 N | 077 31 29 W |
| Riverdale Hills | Populated Place | 33 | Prince George's | 38 57 48 N | 076 54 33 W |
| Riverdale Hills School | School | 35 | Prince George's | 38 57 55 N | 076 54 39 W |
| Riverdale Park | Park | 86 | Baltimore | 39 25 02 N | 076 38 15 W |
| Riverdale Park | Populated Place | 12 | Prince George's | 38 57 48 N | 076 55 54 W |
| Riverdale Park Police Department | Building | | Prince George's | 39 36 18 N | 077 33 24 W |
| Riverdale Plaza Shopping Center | Locale | 19 | Prince George's | 38 57 29 N | 076 55 06 W |
| Riverdale Recreation Center | Park | 9 | Prince George's | 38 57 57 N | 076 55 26 W |
| Rivers Corporate Center | Locale | 92 | Howard | 39 10 12 N | 076 50 60 W |
| Rivers Corporate Park | Locale | 118 | Howard | 39 10 40 N | 076 52 24 W |
| Rivers Edge | Populated Place | 7 | Kent | 39 15 45 N | 075 51 36 W |
| Rivers Ninty Five Industrial Park | Locale | 87 | Howard | 39 10 05 N | 076 50 41 W |
| Rivers Technical Park | Locale | 91 | Howard | 39 10 08 N | 076 50 37 W |
| Rivershore | Populated Place | 8 | Harford | 39 26 23 N | 076 16 03 W |
| Riverside | Populated Place | 3 | Charles | 38 23 16 N | 077 08 47 W |
| Riverside | Populated Place | 24 | Harford | 39 28 25 N | 076 14 29 W |
| Riverside | Populated Place | 98 | Howard | 39 10 24 N | 076 53 07 W |
| Riverside | Populated Place | 3 | Talbot | 38 46 12 N | 076 12 27 W |
| Riverside Business Park | Locale | 24 | Harford | 39 28 45 N | 076 13 59 W |
| Riverside Elementary School | School | 30 | Harford | 39 24 03 N | 076 20 18 W |
| Riverside Estates | Populated Place | 86 | Howard | 39 10 34 N | 076 53 24 W |
| Riverside Homes (subdivision) | Populated Place | 7 | Wicomico | 38 21 35 N | 075 36 37 W |
| Riverside Methodist Church | Church | 8 | Wicomico | 38 21 36 N | 075 36 30 W |
| Riverside Park | Park | 191 | Allegany | 39 38 59 N | 078 45 53 W |
| Riverside Park | Park | 4 | Anne Arundel | 39 14 10 N | 076 37 03 W |
| Riverside Park | Park | 23 | Baltimore (city) | 39 16 13 N | 076 36 29 W |
| Riverside Pines (subdivision) | Populated Place | 6 | Wicomico | 38 20 52 N | 075 37 14 W |
| Riverside Village of Church Creek | Populated Place | 19 | Harford | 39 28 25 N | 076 14 07 W |
| Riverside Wharf | Locale | 30 | Kent | 39 09 41 N | 076 03 12 W |
| Riverside Yard | Locale | 7 | Baltimore (city) | 39 16 05 N | 076 36 12 W |
| Riverton | Populated Place | 2 | Dorchester | 38 34 40 N | 076 14 53 W |
| Riverton | Populated Place | 1 | Wicomico | 38 30 40 N | 075 45 16 W |
| Riverton Acres | Populated Place | 6 | Wicomico | 38 30 17 N | 075 44 34 W |
| Riverton United Methodist Church | Church | 1 | Wicomico | 38 30 40 N | 075 45 10 W |
| Riverview | Populated Place | 13 | Prince George's | 38 43 26 N | 077 01 40 W |
| Riverview | Populated Place | 8 | Queen Anne's | 39 08 42 N | 076 03 51 W |
| Riverview (historical) | Populated Place | 3 | Baltimore (city) | 39 15 27 N | 076 32 24 W |
| Riverview Cemetery | Cemetery | 165 | Washington | 39 41 53 N | 078 09 45 W |
| Riverview Estates | Populated Place | 17 | Prince George's | 38 44 24 N | 077 01 29 W |
| Riverview Gardens (subdivision) | Populated Place | 7 | Caroline | 38 53 17 N | 075 49 49 W |
| Riverview Manor | Populated Place | 13 | Anne Arundel | 38 59 53 N | 076 30 31 W |
| Riverview Park | Park | 34 | Baltimore | 39 14 08 N | 076 39 24 W |
| Riverview Recreation Center | Park | 24 | Prince George's | 38 44 22 N | 077 00 38 W |
| Riverview School | School | 32 | Baltimore | 39 14 10 N | 076 39 19 W |
| Riverview Village | Populated Place | 12 | Charles | 38 36 20 N | 077 09 57 W |
| Riverwood | Populated Place | 19 | Anne Arundel | 38 55 00 N | 076 40 21 W |
| Riverwood | Populated Place | 93 | Frederick | 39 21 16 N | 077 21 23 W |
| Riverwood | Populated Place | 85 | Montgomery | 39 04 20 N | 077 18 14 W |
| Riverwood Farms | Populated Place | 27 | St. Mary's | 38 24 24 N | 076 37 14 W |
| Riverwood Park | Park | 22 | Anne Arundel | 38 55 01 N | 076 40 09 W |
| Riverwood Park | Populated Place | 12 | Baltimore | 39 18 43 N | 076 26 39 W |
| Rives | Populated Place | 22 | Prince George's | 38 55 53 N | 076 57 24 W |
| Riviera Beach | Populated Place | 3 | Anne Arundel | 39 10 00 N | 076 30 29 W |
| Riviera Beach Branch Library | Building | 18 | Anne Arundel | 39 08 43 N | 076 31 36 W |
| Riviera Beach Cemetery | Cemetery | 7 | Anne Arundel | 39 09 59 N | 076 30 58 W |
| Riviera Beach Fire Company 13 | Building | | Anne Arundel | 39 09 24 N | 076 31 03 W |
| Riviera Beach Post Office | Post Office | 7 | Anne Arundel | 39 09 25 N | 076 31 05 W |
| Riviera Beach School | School | 10 | Anne Arundel | 39 09 32 N | 076 30 42 W |
| Riviera Beach Volunteer Fire Company 13 | Building | | Anne Arundel | 39 16 08 N | 076 52 05 W |
| Riviera Isle | Populated Place | 9 | Anne Arundel | 39 08 19 N | 076 31 14 W |
| Riviera Plaza Shopping Center | Locale | 7 | Anne Arundel | 39 09 29 N | 076 30 59 W |
| Roach Point | Cape | 1 | Cecil | 39 32 34 N | 075 58 09 W |
| Roaches Run Park | Park | 182 | Baltimore | 39 26 35 N | 076 48 29 W |
| Roachs Shore | Beach | -9 | Cecil | 39 32 33 N | 075 58 10 W |
| Roaring Point | Cape | 0 | Wicomico | 38 15 52 N | 075 55 09 W |
| Roaring Run | Stream | | Carroll | 39 30 36 N | 076 53 15 W |
| Roaring Run Community Park | Park | 158 | Carroll | 39 29 15 N | 076 52 49 W |
| Roasting Ear Point | Cape | 0 | Dorchester | 38 16 52 N | 076 01 38 W |
| Rob Vanary Park | Park | 7 | Kent | 39 15 36 N | 075 50 37 W |
| Robbins | Populated Place | 0 | Dorchester | 38 22 32 N | 076 04 32 W |
| Robbins Landing | Populated Place | 0 | Dorchester | 38 22 37 N | 076 03 29 W |
| Robbins Tump | Island | 0 | Worcester | 38 04 39 N | 075 18 36 W |
| Robert Brown Elliott Public School (historical) | School | 60 | Baltimore (city) | 39 18 22 N | 076 38 22 W |
| Robert Coleman Elementary School | School | 72 | Baltimore (city) | 39 18 37 N | 076 39 12 W |
| Robert Crown Sailing Center | Building | 0 | Anne Arundel | 38 58 56 N | 076 28 40 W |
| Robert E Lee Junior High School (historical) | School | 27 | Baltimore (city) | 39 18 14 N | 076 37 05 W |
| Robert E Lee Park | Park | 97 | Baltimore | 39 23 15 N | 076 39 06 W |
| Robert E Peary High School (historical) | School | 102 | Montgomery | 39 04 24 N | 077 06 03 W |
| Robert Eden Public School (historical) | School | 41 | Baltimore (city) | 39 18 31 N | 076 35 58 W |
| Robert Frost Elementary School | School | 34 | Prince George's | 38 58 33 N | 076 52 31 W |
| Robert Frost Middle School | School | 120 | Montgomery | 39 04 33 N | 077 11 16 W |
| Robert Goddard Middle School | School | 49 | Prince George's | 38 59 12 N | 076 50 30 W |
| Robert Island | Island | 5 | Harford | 39 36 52 N | 076 08 24 W |
| Robert M Watkins Regional State Park | Park | 37 | Prince George's | 38 53 19 N | 076 47 41 W |
| Robert Morton Elementary School | School | 273 | Carroll | 39 32 07 N | 076 59 35 W |
| Robert Moton School | School | 230 | Carroll | 39 34 00 N | 076 59 47 W |
| Robert Poole Middle School | School | 63 | Baltimore (city) | 39 19 51 N | 076 38 17 W |
| Robert R Gray Elementary School | School | 30 | Prince George's | 38 54 36 N | 076 55 19 W |
| Robert Stethem Memorial Complex | Park | 55 | Charles | 38 35 20 N | 076 53 08 W |
| Roberto Clemento Middle School | School | 131 | Montgomery | 39 09 56 N | 077 14 47 W |
| Roberts | Populated Place | 206 | Allegany | 39 37 52 N | 078 48 13 W |
| Roberts | Populated Place | 20 | Queen Anne's | 39 07 02 N | 075 55 06 W |
| Roberts Cemetery | Cemetery | 19 | Talbot | 38 43 09 N | 076 02 55 W |
| Roberts Field (subdivision) | Populated Place | 239 | Carroll | 39 35 57 N | 076 50 24 W |
| Roberts Field Business Center | Locale | 255 | Carroll | 39 35 40 N | 076 50 37 W |