| Aldenham Country Park | 70.01 ha | | — |
| Elstree Open Space | 44.17 ha | | — |
| Deacons Hill Open Space | 43.59 ha | | — |
| Bushey Manor Field | 12.42 ha | | — |
| Woodcock Hill Village Green | 9.86 ha | | — |
| Parkfield | 9.84 ha | | — |
| Morven Park National Trust | 9.31 ha | | — |
| Aberford Park | 6.89 ha | | — |
| Oakmere Park | 6.53 ha | | — |
| Composers Park | 6.46 ha | | — |
| Meadow Park | 5.1 ha | | — |
| Moatfield Recreation Ground | 4.79 ha | | — |
| Local Wildlife Site (Herts LA) | 4.39 ha | | — |
| Ripon Park | 4.32 ha | | — |
| Tempsford Green | 3.88 ha | | — |
| Maxwell Park | 3.45 ha | | — |
| Thirskcliffe Nature Park | 3.0 ha | | — |
| Local Wildlife Site (Herts LA) | 2.73 ha | | — |
| King George Playing Field | 2.63 ha | | — |
| Brook Meadow | 2.24 ha | | — |
| Wash Lane Common Nature Reserve Hertsmere Borough Council | 1.88 ha | | — |
| Fishers Field Nature Reserve | 1.81 ha | | — |
| Hill Mead Nature Park | 1.29 ha | | — |
| Grace Avenue Public Open space | 0.95 ha | | — |
| Shenley Park Walled Garden | 0.8 ha | | — |
| Mary Forsdyke Gardens | 0.71 ha | | — |
| Bushey Rose Garden | 0.52 ha | | — |
| Shenley Park | 0.51 ha | | — |
| Willow Way Park | 0.41 ha | | — |
| Clarendon Park | 0.3 ha | | — |
| Rose Garden | 0.06 ha | | — |
| Hartforde Road common ground | 0.05 ha | | — |
| The Sunken Garden | 0.05 ha | | — |
| Community Peace Garden | 0.03 ha | | — |
| Potters Bar Memorial Gardens | 0.02 ha | | — |