Feature Name | Class | Elev. meters | County | Latitude DMS | Longitude DMS |
| Jefferson School | School | 24 | Mercer | 40 13 50 N | 074 45 31 W |
| John S Watson Park | Park | 40 | Mercer | 40 16 20 N | 074 47 52 W |
| John V B Wicoff Elementary School | School | 40 | Mercer | 40 19 59 N | 074 35 37 W |
| John Witherspoon Middle School | School | 56 | Mercer | 40 21 11 N | 074 39 46 W |
| Johnson Park School | School | 35 | Mercer | 40 20 55 N | 074 41 04 W |
| Junior High School Number 1 | School | 29 | Mercer | 40 13 55 N | 074 45 36 W |
| Junior High School Number 5 | School | 21 | Mercer | 40 13 33 N | 074 45 46 W |
| Kendall Hall | Building | 40 | Mercer | 40 16 13 N | 074 46 46 W |
| Key and Seal Club (historical) | Building | 51 | Mercer | 40 20 56 N | 074 38 58 W |
| Ksayian | Airport | 97 | Mercer | 40 22 00 N | 074 50 59 W |
| Lakeside Park | Populated Place | 22 | Mercer | 40 11 34 N | 074 41 14 W |
| Lalor School | School | 14 | Mercer | 40 11 46 N | 074 44 27 W |
| Lanning School | School | 36 | Mercer | 40 16 00 N | 074 47 03 W |
| Lawrence | Populated Place | 18 | Mercer | 40 16 26 N | 074 40 47 W |
| Lawrence High School | School | 30 | Mercer | 40 15 55 N | 074 43 51 W |
| Lawrence Intermediate School | School | 40 | Mercer | 40 16 23 N | 074 44 21 W |
| Lawrence Middle School | School | 31 | Mercer | 40 15 46 N | 074 43 57 W |
| Lawrence Shopping Center | Locale | 40 | Mercer | 40 15 32 N | 074 43 47 W |
| Lawrenceville | Populated Place | 36 | Mercer | 40 17 50 N | 074 43 47 W |
| Lawrenceville Cemetery | Cemetery | 49 | Mercer | 40 18 26 N | 074 43 19 W |
| Lawrenceville Elementary School | School | 40 | Mercer | 40 17 55 N | 074 43 58 W |
| Lawrenceville School | School | 32 | Mercer | 40 17 38 N | 074 43 45 W |
| Lenox House | Building | 60 | Mercer | 40 20 46 N | 074 40 02 W |
| Lewis Brook | Stream | | Mercer | 40 20 00 N | 074 46 54 W |
| Lewisville | Populated Place | 33 | Mercer | 40 17 20 N | 074 43 34 W |
| Lions Park | Park | 40 | Mercer | 40 16 01 N | 074 46 45 W |
| Lions Stadium | Park | 40 | Mercer | 40 16 04 N | 074 46 41 W |
| Little Shabakunk Creek | Stream | | Mercer | 40 15 50 N | 074 42 54 W |
| Littlebrook Elementary School | School | 32 | Mercer | 40 21 50 N | 074 38 16 W |
| Locust Corner | Populated Place | 31 | Mercer | 40 17 04 N | 074 33 42 W |
| Lourie - Love Hall | Building | 44 | Mercer | 40 20 40 N | 074 39 22 W |
| Lower Pyne | Building | 61 | Mercer | 40 21 00 N | 074 39 34 W |
| Mackay Campus Center | Building | 58 | Mercer | 40 20 39 N | 074 39 48 W |
| MacLean House | Building | 62 | Mercer | 40 20 57 N | 074 39 37 W |
| Marie H Katzenbach State School for the Deaf | School | 33 | Mercer | 40 15 24 N | 074 48 40 W |
| Marquand Chapel (historical) | Church | 62 | Mercer | 40 20 56 N | 074 39 24 W |
| Marshalls Corner | Populated Place | 67 | Mercer | 40 21 41 N | 074 47 46 W |
| Mather Sundial | Unknown | 63 | Mercer | 40 20 55 N | 074 39 24 W |
| Maurice H Hawn Elementary School | School | 30 | Mercer | 40 18 24 N | 074 37 34 W |
| McCauley House | Building | 40 | Mercer | 40 16 14 N | 074 47 01 W |
| McCormick Hall | Building | 61 | Mercer | 40 20 50 N | 074 39 28 W |
| McCosh Hall | Building | 63 | Mercer | 40 20 54 N | 074 39 22 W |
| McDonnell Hall | Building | 39 | Mercer | 40 20 43 N | 074 39 07 W |
| McKinley Hospital | Hospital | 25 | Mercer | 40 14 09 N | 074 45 08 W |
| Meadow Lakes | Reservoir | 30 | Mercer | 40 15 35 N | 074 31 08 W |
| Meadows Terrace | Populated Place | 30 | Mercer | 40 14 32 N | 074 36 06 W |
| Melvin H Kreps Middle School | School | 30 | Mercer | 40 16 24 N | 074 33 45 W |
| Memorial Hall | Building | 61 | Mercer | 40 20 55 N | 074 39 33 W |
| Mercer Cemetery | Cemetery | 14 | Mercer | 40 13 10 N | 074 45 22 W |
| Mercer County | Civil | 130 | Mercer | 40 23 00 N | 074 52 59 W |
| Mercer County Airport | Airport | 57 | Mercer | 40 16 36 N | 074 48 47 W |
| Mercer County Community College | School | 30 | Mercer | 40 15 15 N | 074 39 06 W |
| Mercer County Junior-Senior High School | School | 31 | Mercer | 40 15 10 N | 074 39 29 W |
| Mercer County Lake | Reservoir | 18 | Mercer | 40 16 10 N | 074 38 39 W |
| Mercer County Park | Park | 23 | Mercer | 40 16 26 N | 074 38 44 W |
| Mercer County Park | Park | 40 | Mercer | 40 20 05 N | 074 54 59 W |
| Mercer County Vocational School Sypek Center | School | 40 | Mercer | 40 17 13 N | 074 46 06 W |
| Mercer Hospital | Hospital | 24 | Mercer | 40 13 51 N | 074 46 41 W |
| Mercer Mall Shopping Center | Locale | 25 | Mercer | 40 17 52 N | 074 41 07 W |
| Mercer Medical Center | Airport | 29 | Mercer | 40 13 49 N | 074 46 34 W |
| Mercer Oaks Golf Course | Locale | 40 | Mercer | 40 16 33 N | 074 39 56 W |
| Mercerville | Populated Place | 27 | Mercer | 40 14 13 N | 074 41 12 W |
| Miller Chapel | Church | 61 | Mercer | 40 20 43 N | 074 39 48 W |
| Millstone | Populated Place | 29 | Mercer | 40 17 17 N | 074 31 54 W |
| Miry Run | Stream | | Mercer | 40 14 58 N | 074 43 05 W |
| Monument Schools | School | 25 | Mercer | 40 13 42 N | 074 46 08 W |
| Moody Park | Park | 33 | Mercer | 40 15 15 N | 074 45 51 W |
| Moon Channel | Channel | 6 | Mercer | 40 11 18 N | 074 45 25 W |
| Moore | Populated Place | 26 | Mercer | 40 19 27 N | 074 54 53 W |
| Moores Creek | Stream | | Mercer | 40 19 23 N | 074 55 03 W |
| Morris Church | Church | 37 | Mercer | 40 17 16 N | 074 44 04 W |
| Morris Hall Cemetery | Cemetery | 37 | Mercer | 40 17 17 N | 074 44 09 W |
| Morven | Building | 61 | Mercer | 40 20 50 N | 074 39 59 W |
| Mott School | School | 7 | Mercer | 40 12 03 N | 074 45 26 W |
| Mount Canoe | Summit | 127 | Mercer | 40 19 57 N | 074 51 25 W |
| Mount Olivet Baptist Church | Church | 30 | Mercer | 40 16 27 N | 074 31 31 W |
| Mount Rose | Populated Place | 91 | Mercer | 40 22 09 N | 074 44 21 W |
| Mount Rose | Summit | 125 | Mercer | 40 22 02 N | 074 43 21 W |
| Mount Zion Church | Church | 34 | Mercer | 40 15 36 N | 074 32 24 W |
| Mountain Lake | Lake | 50 | Mercer | 40 21 38 N | 074 40 42 W |
| Mountain View Golf Course | Locale | 40 | Mercer | 40 16 59 N | 074 49 42 W |
| MountainView Office Park | Locale | 40 | Mercer | 40 16 45 N | 074 49 43 W |
| Murray Hall | Building | 63 | Mercer | 40 20 53 N | 074 39 27 W |
| Nassau Hall | Building | 62 | Mercer | 40 20 56 N | 074 39 33 W |
| Nassau Presbyterian Church | Church | 62 | Mercer | 40 20 56 N | 074 39 38 W |
| Naussau Industrial Park | Locale | 40 | Mercer | 40 18 07 N | 074 40 44 W |
| New Hope Church | Church | 33 | Mercer | 40 16 12 N | 074 45 13 W |
| New Jersey Regional Day School at Hamilton | School | 30 | Mercer | 40 15 06 N | 074 39 29 W |
| New Jersey State Prison Farm | Locale | 40 | Mercer | 40 16 16 N | 074 49 40 W |
| Norsworthy House | Building | 40 | Mercer | 40 16 11 N | 074 46 28 W |
| North Court | Building | 55 | Mercer | 40 20 29 N | 074 39 55 W |
| North Crosswicks | Populated Place | 15 | Mercer | 40 09 32 N | 074 38 52 W |
| North Princeton | Populated Place | 53 | Mercer | 40 21 50 N | 074 39 40 W |
| North Trenton Park | Park | 30 | Mercer | 40 13 47 N | 074 45 38 W |
| Notestein Hall | Building | 57 | Mercer | 40 20 52 N | 074 39 12 W |
| Notre Dame High School | School | 21 | Mercer | 40 15 19 N | 074 44 37 W |
| Nottingham | Populated Place | 25 | Mercer | 40 13 57 N | 074 40 55 W |
| Old Mill Farms | Populated Place | 21 | Mercer | 40 18 54 N | 074 36 14 W |
| Old Mill Road County Park | Park | 43 | Mercer | 40 19 53 N | 074 46 04 W |
| Our Lady of Princeton Convent | Church | 114 | Mercer | 40 22 34 N | 074 42 06 W |
| Packer Hall | Building | 40 | Mercer | 40 16 08 N | 074 46 41 W |
| Palmer Hall | Building | 58 | Mercer | 40 20 49 N | 074 39 18 W |
| Palmer Lake | Lake | 38 | Mercer | 40 21 42 N | 074 40 35 W |
| Palmer Square | Park | 59 | Mercer | 40 21 02 N | 074 39 41 W |
| Palmer Stadium | Park | 37 | Mercer | 40 20 44 N | 074 38 60 W |
| Parker School | School | 7 | Mercer | 40 12 33 N | 074 45 50 W |
| Parkway School | School | 32 | Mercer | 40 14 33 N | 074 46 47 W |
| Parkway Village | Populated Place | 38 | Mercer | 40 15 33 N | 074 47 19 W |
| Paul Loser Hall | Building | 40 | Mercer | 40 16 07 N | 074 46 52 W |
| Peddie Country Club | Locale | 36 | Mercer | 40 15 12 N | 074 31 18 W |