The theme of the poem is how Yeats wants to live peacefully in isolation in a place called Innisfree. Maybe he thinks that this will make him a better poet.
The image in the poem is that the poet is on the busy streets of London when he dreams of a bee hive and a cabin on the Lake Isle of Innisfree. Life is just a whole lot slower there.
In reality it is grey and dull in London and over there he is rushing to home and work.
At least Inisfree will always be in his heart.
By Luke Lewis