Ah, the famous red phone box. Symbol of London, but found all over the country.
The box as we know it was designed by Giles Gilbert Scott, supposedly inspired by the tomb of Sir John Soane in St Pancras churchyard.
The 'K2', as it was called, was not the first phone box, and by no means the last. In this illustration, we chart the different species of kiosk to appear on our streets. The main diagonal in the image shows the 'official' lineage of phone boxes commissioned by the General Post Office and later BT. Side branches are more whimsical.
In recent years, the need for phone boxes has greatly diminished. Many have been put to new and novel use, such as book swaps, work desks and even sushi stalls. Meanwhile, artists such as Banksy have changed the (dialling) tone with creative works of phone box art.
The latest and much-derided successor to the K2 is the Link from BT. These sleek monoliths offer free calls, phone charging, ultrafast wifi and other digital services, so long as you're happy to share your data with a range of companies. Is this the last gasp in the hundred-year evolution of the phone booth?
For more on the main sequence of phone boxes in our image, see this excellent chronology of the phone box.
Photos: Most images are by the author or public domain. Exceptions are as follows. K1 by Josling. K3 by Martin Pettitt. K5 by BowBelle51. K8 by Oxyman, all under creative commons licence. Link is from a publicity photo via BT.