The chalk ridge of the North Downs runs west to east across Surrey like a fold in the landscape, dividing the county in two. North of the Downs lies the Thames basin, flat and now mostly suburban, the commuter belt of greater London. South of the Downs is the Weald, the ancient forest that once covered the borders of Surrey, Sussex, and Kent. Leith Hill near Dorking rises to 294 metres and is the second-highest point in southern England. The North Downs Way runs along the crest. The chalk is pierced by two rivers, the Wey and the Mole, both tributaries of the Thames. The county has the densest woodland cover in England at over 22 per cent, and the Surrey Heath district leads the country with 41 per cent tree cover. Before the Romans, the area was probably Atrebates territory, with the south-eastern fringes held by the Cantiaci. The Romans built a temple complex at Farley Heath and another near Wanborough, and ran Stane Street straight from London to Chichester through Dorking.

In 1036, in a Surrey town called Guildford, a Saxon atrocity took place that the chronicles still describe with horror. Alfred Ætheling, son of Æthelred the Unready, had returned from exile in Normandy with a small retinue. Earl Godwin of Wessex met him in apparent friendship, escorted him to Guildford for the night, and at dawn the prince's men were attacked in their lodgings. Most were killed, mutilated, or sold into slavery. Alfred was blinded and imprisoned, and died of his wounds. His brother, Edward the Confessor, never forgot. The repercussions of that Guildford morning helped tip England into the Norman Conquest thirty years later. Surrey had been a contested frontier shire for centuries by then, fought over between Kent, Essex, Sussex, Wessex, and Mercia, until Wessex absorbed it for good in 825. King Æthelstan was crowned at Kingston upon Thames in 924. Æthelred the Unready was crowned there in 978. Kingston still calls itself the coronation town.

Surrey has a curious habit of being where English political ideas crystallise. Runnymede gave the world Magna Carta in 1215. In October 1647, in the Surrey town of Putney (then in Surrey, now in London), Oliver Cromwell and the senior officers of the New Model Army met with their own rank and file to argue over the future of the nation. The Putney Debates produced what became the Agreement of the People, a draft constitution founded on popular sovereignty. Two years later, on St George's Hill near Weybridge, a small group led by Gerrard Winstanley began digging up common land to plant vegetables. They called themselves the True Levellers; their critics called them the Diggers. They believed land should be held in common and that the English Civil War had been fought, in part, to end private property. Local landowners drove them out within months with beatings and lawsuits, and a smaller commune at Cobham fell the same way in 1650. The Diggers failed at almost every practical level. Their writings became foundational texts for English socialism three centuries later.

Surrey did innovation in its own quiet way. Brookwood Cemetery near Woking, opened in 1849 to serve London's overflowing graveyards, had its own railway connection from the capital and became the largest burial ground in the world. Woking also opened Britain's first crematorium in 1878 and Britain's first mosque, the Shah Jahan, in 1889. In 1881 Godalming became the first town anywhere in the world with a public electricity supply. Brooklands, between Woking and Weybridge, opened in 1907 as the world's first purpose-built motor-racing circuit. Aircraft followed. The Sopwith Aviation Company started there in 1912, evolved through Hawker Siddeley, and built fighters used in two world wars. McLaren's Formula One headquarters are at Woking today. Surrey, for all its reputation as the stockbroker belt, has spent a century quietly inventing the future.

Modern Surrey runs from Staines on the Thames in the north to Haslemere in the south-west, with Woking as its largest town and Guildford as its historic county town. The Surrey Hills are an Area of Outstanding Natural Beauty. Box Hill, just north of Dorking, was the picnic spot in Jane Austen's Emma where Mr Knightley scolded the heroine for being unkind to Miss Bates. The Devil's Punch Bowl at Hindhead, until 2011 a notorious A3 bottleneck, is now restored to heath after the Hindhead Tunnel buried the old road. H.G. Wells set the opening of The War of the Worlds on Horsell Common near Woking, and a tall metal sculpture of the Martian tripod now stands in the town. The fictional Little Whinging, where Harry Potter spent his miserable childhood, is somewhere in Surrey too. So is the cathedral at Guildford, on its hill, where they filmed The Omen. The county is famous for what is normal here. It keeps the unusual very well hidden.