London Underground by Design – in pictures

An underground advertisement with map, 1908-16. Photograph: London Underground by Design

The blueprint for a vertical logo, 1908-9. Photograph: London Underground by Design

Chiswick Park station opened in April 1932. Photograph: London Underground by Design

Escalator mazes by Nicolas Monroe at Oxford Circus (1983). Photograph: London Underground by Design

Green Park, the greenest central London tube entrance. Photograph: London Underground by Design

Highgate station (renamed Archway a few years later) was reopened with Charles Holden's huge glazed wall frontage in April 1932. Photograph: London Underground by Design

The red discs were rolled out 1918-15. Photograph: London Underground by Design

The stairway at King's Cross, 1925. Photograph: London Underground by Design

A digital reconstruction of the once ubiquitous hexagonal lamps with 'UndergrounD' marking. Photograph: London Underground by Design

Met serifs, 1920s. Photograph: London Underground by Design

Combined logo on signage at Paddington (digitally re-coloured), 1913-15. Photograph: London Underground by Design

Mark Lane station (later re-sited and renamed Tower Hill), 1907. Photograph: London Underground by Design

Leslie William Green's pioneering design wasn't simply about pretty tiling; his styling permeated every step of the passengers' journey, from ticket hall to exit signs. 1906-8. Photograph: London Underground by Design

Morden station in 1925, with a wooden mock-up of Charles Holden's adaptable frontage. Construction began the same year. Photograph: London Underground by Design

The Met's red diamond, 1917-29. Photograph: London Underground by Design