Coming in at number six is the North Downs.

The M25, one of the busiest roads in Britain, thunders along, right beside the ridge of the North Downs.

Pilgrims used to find their way to Canterbury by following the North Downs Way.

Since Neolithic times, several thousand years before the birth of Christ, travellers and tradesmen from the ports of the South East, followed the upper chalk ridge en route to the heart of England.

They are called the Downs because they are the uplands of Kent. If that doesn't make sense, the reason for that is the word "down" is from the old Dutch word "doon" which means a ridge.

In the stone age there would have been people walking along these downs, probably all the way as far as Stonehenge, through the whole of North Kent, through Surrey, onto Salisbury Plain and back again.

And during the Ice Age our distant ancestors, could have walked all the way from France, right across the English Channel, all the way to Kent.

Eighty million years ago this was once the seabed of a crustaceous chalk sea.

Then some 50m years ago, Italy collided with Europe, pushing up the Alps and the great pressure buckled the whole of southern England so that this chalk would have risen about a kilometre into the sky, arched over the entire Weald, over Folkestone and come down the other side on the South Downs

This is a particularly rich site for chalk grassland. The chalk supports cowslips, common spotted orchids, early purple orchids, bee orchids, harebells and marjoram.