Perched atop Highgate Hill, Cromwell Avenue is surely the most elegant of eyries. There’s a wistful wonder to this part of the city, the wilderness of Hampstead Heath, the mossy tombs of Highgate cemetery, the tall, imposing houses gazing down onto the grey pavements below.

Here is the London of books and poetry, of memories and ghosts. Clatter up the stairs where the eaves look out over roofs and leaves, throw open the windows, and dream.