We use the to refer to certain geographical features by name.
We use the to refer to some geographical features in the plural only.
| Singular | Plural | |
| Mountains | Mount Everest | the Alps | 
| Islands | Pitcairn Island | the Philippines | 
We use the with valleys only when valley is the first word.
| Singular | Plural | |
| Valley | Death Valley | the Valley of Flowers |