The British photographer Paul Graham embarked on a long road trip in 1981. Twenty years after the publication of Robert Frank’s The Americans – which along with Jack Kerouac’s On the Road immortalised the Great American Road Trip – Graham started his journey in the City of London and followed the A1 for 400 miles through the industrial north and on to Edinburgh.

The route has been used since Roman times and was the mail coach route between London, York and Edinburgh before becoming the busiest motorway in Britain until it was supplanted by the newly built M1. The collection of photographs that document the A1 and its slide into obscurity, called A1: The Great North Road, appear in Graham’s eponymous first book, self-published in 1983. Some are in the first room of the photographer’s retrospective at the Whitechapel Gallery in east London.

The series takes in young City workers outside the Bank of England, with a blue tie blowing in the wind; a woman waiting at a graffitied bus stop in Mill Hill, north London; a Little Chef in the rain and two men hanging out in a bus converted to a cafe in West Yorkshire. I love the contrast between Graham’s tacky service stations and Frank’s sleek diners; the A1 hemmed in by rundown houses, railway lines and power stations against America’s wide open highways with only a speck of a car on the horizon. Contrast the greyness of this vision with the slick, colourful images the British photographer took of suburban America two decades later.

Graham, born in 1956, was one of the first to use colour for documentary photography, traditionally in black and white, in the early 1980s. Martin Parr moved to colour soon after – his saturated photographs of seaside Britain would be unthinkable in black and white.

To say that Graham has an eye for detail would be underplaying his work. His landscape shots of Northern Ireland from the Troubled Land series of 1985-86 are littered with subtle reminders of the Troubles. At first glance, the pictures look like idyllic landscapes with lush green scenery, but when you look closer you notice the Union Jack at the top of a tree, Unionist posters in another tree, a Republican parade in a small town and soldiers doing a stop and search on a passing car.

Initially Graham had taken the usual shots of huge murals on both sides in Belfast. Somewhat frustrated, he then took a picture of a roundabout with a soldier running off in the distance, despite being told off by the British army patrol. Later he realised that this was the kind of image he wanted to create.

There is nothing more exciting than looking at these pictures and deciphering them through the tiny clues hidden in them – a bit like ‘reading’ a Renaissance landscape or a Hieronymus Bosch painting.

Graham also has an eye for humorous moments. The series of photographs taken at DHSS benefits offices around Britain, entitled Beyond Caring (1984-85), includes a crowded waiting room where one man is scrutinising a Page 3 girl in the Sun, while other people around him are dozing or staring into nothingness. Another image shows a toddler in the middle of a waiting room glancing curiously at the elderly people with walking sticks seated around her.

The photographer says: “I realised that concealment… has run through… my work, from the landscape of Northern Ireland, and the unemployed tucked away in backstreet offices, to the burdens of history swept under the carpet in Europe or Japan. Concealment of our turmoil from others, from ourselves even.”

The New Europe series from 1988-90 sprang from two years of travelling across nine countries and contains diverse images such as spit on Franco’s grave, a woman in Northern Ireland enjoying a cigarette with complete abandonment and a prostitute embracing her pimp.

As the gallery states: “The everyday scenarios he reflects are also embedded with a complex iconography. The hand that an immaculately made up Japanese girl waves across her mouth evokes a society anxiously over-invested in surfaces.”

In the 90s Graham’s photography shifted, becoming less specific and less overtly political. End of an Age, 1996-98, is a series of often blurry, atmospheric portraits of young people in bars and clubs in an anonymous European city, reaching adulthood just before the millennium. American Night (1998-2003) gives us overexposed, near invisible white images of the American dream. Images of black neighbourhoods so white they’ve almost been wiped out, juxtaposed with saturated photos of wealthy suburban homes.

In the late 1990s, Graham spent more of his time in the US and eventually moved to New York in 2002. A shimmer of possibility, 2004-06, records moments from everyday life spotted on his journeys across America – for example a black gardener mowing the lawn beside a carpark – as sequences of images showing the same scene from different perspectives, which Graham calls little ‘filmic haiku’ (or photographic short stories). Despite his constant movement, traversing back and forth, the gardener is going nowhere.

Graham’s most powerful images, though, are in his earlier work, from Northern Ireland to benefits offices. The seemingly romantic landscape scenes turn out to be war reportage in disguise. Later, he took pictures of the sky in hotspots such as Cavan and Derry during the first ceasefire in Northern Ireland in 1994 – most of them looking gloomy and foreboding, as one might expect.

Paul Graham: Photographs 1981-2006 is at the Whitechapel Gallery until 19 June. Admission free.