It's 70 degrees in the shade and I'm on my hands and knees, sifting through a field of dried mud, hunting for diamonds. A trip to a jeweller would have been easier, but where would be the fun in that?

I'm in one of the USA's more unusual tourist attractions, Crater of Diamonds State Park, deep in rural Arkansas. It's the only official diamond-mining site in the world where you get to dig yourself - and keep what you find! 'Uncle Sam', at more than 40 carats the largest diamond ever unearthed in North America, was found right here on this 37-acre site, the eroded surface of an ancient volcano pipe. Last year alone there were 1,024 diamond finds - that's nearly three each day.

Those sound like good odds, but today must be somebody else's lucky day. Not that I'm downcast, because I reckon I've already found something of a hidden jewel in this Southern state.

Many people in the UK associate Arkansas with just one thing - former US President Bill Clinton - and the state has not been slow to capitalise on its favourite son.

Just down the road from Crater of Diamonds is the small house where Clinton was born in 1946. The house itself has plenty of charm, but it's not until my guide tells me (in a matter-of-fact tone) that she's a family friend who 'used to change Bill's diapers' that I have my first double-take moment.

The small-town feel of Hope contrasts with the Clinton Presidential Center in Arkansas' capital city, Little Rock. This impressive, ultra-modern building is home to the largest collection of Presidential documents anywhere in the USA, and there's something to capture the attention of anyone with even a passing interest in the 1990s.

A full-size replica of the Oval Office, decorated exactly as it was during the Clinton years makes a popular tourist attraction. It's a little-known White House tradition that each President redecorates the room on taking office, although one assumes the world's most powerful man doesn't actually wield the paintbrush.

The part of the Clinton Center you don't get to see is at the very top, where a luxury penthouse is home to the ex-President on his regular trips back to Little Rock. The locals tell me he comes back at least once a month from his New York base.

"Last year alone there were 1,024 diamond finds - that's nearly three each day."

Not surprisingly, you can find Clinton paraphernalia all over Arkansas; there's even a 'Billgrimage' (I kid you not) trail which links key sites across the state related to the great man. But Arkansas is about much more than just an ex-President.

As you'd expect in the South, there are heritage attractions in spades. In fact, travelling through Arkansas is very much like taking a trip through American history.

The Arkansas River, a major tributary of the Mississippi, flows through Little Rock and is an ever-present reminder of how this part of the USA was first explored, then settled in the 18th and early 19th centuries.

Civil War action took place here too, with battlefield sites across the state. Fort Smith, on Arkansas' western border with Oklahoma, was a key strategic location during the conflict, but achieved greater notoriety during the 1880s and 1890s.

During this period Fort Smith was the last bastion of civilisation before the lawless territory to the West. Much-feared 'Hangin' Judge' Isaac C Parker dispensed firm justice and his gaol became known as 'Hell on the Border'. At Fort Smith National Historic Site a visit to Parker's gaol, courtroom and gallows brings those turbulent years to life.

Back in Little Rock the more recent past takes over. In the BC times (Before Clinton) Arkansas' capital was best known for the desegregation crisis of 1957, when nine black students attempted to enrol at the whites-only Little Rock Central High School.

With local feelings running high, political points at stake and a mob on the streets each morning, only the personal intervention of President Eisenhower saved the situation. The President called in the US Army 101st Airborne Division to escort the 'Little Rock Nine' to school and to ensure their safety, and the episode went down in history as one of the key moments in the Civil Rights struggle.

Last year a new visitors' museum opened to mark the 50th anniversary, and its newspaper reports, photographs and video footage provide plenty of food for thought. I'm shown around the exhibition and the school itself by ranger Spirit Trickey, who is well-placed to offer further insight; her mother, Minniejean Brown, was one of the nine students.

"Not surprisingly, you can find Clinton paraphernalia all over Arkansas; there's even a 'Billgrimage' trail."

This kind of connection with living history is one of the things that makes Arkansas special - it's small enough, and friendly enough, for a visitor like me to meet people who changed a President's diapers, or whose family were involved in events that transformed the world.

Another is its unspoiled beauty. Arkansas is known as 'The Natural State', but I'd call it a giant playground. More than 60 per cent of the state is covered by forests and there are around 600,000 acres of lakes and nearly 10,000 miles of rivers and streams. Hiking, canoeing, rafting, biking and horse-riding are all hugely popular and easily accessible.

Best of all, at 53,000 square miles the state is roughly the size of England - but where England has nearly 50 million inhabitants, Arkansas has fewer than three million. If you want to escape the crowds and get out in the open air, this is the place.

My best moment? Winding down after a great day hiking the trails at Mount Magazine State Park. I'm sipping a beer at the state-owned Lodge overlooking the beautiful Petit Jean River Valley and Blue Mountain Lake, I'm completely relaxed, and looking forward to what tomorrow will bring.

If that's not natural, I don't know what is.

By Paul Preston

For more information on Arkansas, visit www.arkansas.com. Tour operators including North America Travel Service (0113 243 0000) sell fly-drive holidays to the state.