Curtis Le May must be forever spinning in his grave. He probably deserves to be. He was the US general under Presidents Kennedy and Johnson who threatened to bomb Vietnam back to the Stone Age. Nice guy. And he gave it a good try. Seven million tons of bombs were dropped on Vietnam, Laos and Cambodia – more than twice the amount of explosives dropped on Europe and Asia in the Second World War.

But amazingly, it didn’t work. Not only did the Vietnamese stubbornly fail to be destroyed, they won the war. How on earth could a relatively small, poor, underdeveloped country defy the might of the most powerful nation on earth and send them packing?

Ten minutes spent exploring the tunnels at Cu Chi about 40 miles from Ho Chi Minh City (formerly Saigon) reveals the answer. The Vietnamese started digging the tunnels in the 1940s and at their peak in the 60s, they covered hundreds of kilometres, at one point stretching from HCMC nearly to the Cambodia border.

In the Tunnels

Now, one section of the tunnels is a tourist attraction. You could dismiss it as turning the horror of war into little more than a theme park. And there is a cafe, a souvenir shop where you can buy Vietcong hats and scarves and figures fashioned out of bullets. You can even have a go at firing an AK47.

But it’s much more than that. You could see it as offering a unique insight into how one of the most bloody, devastating and ultimately pointless wars in human history was won and lost. And the tunnels also shine a light on the Vietnamese character.

They were carved out of the dense clay by men and women with the most primitive tools, little more than tin plates and scoops, in the most difficult and terrifying circumstances. You can only guess how tough and determined they must have been.

The tunnels didn’t just cover huge distances. They were on three levels and level three, metres deep into the earth, was where they took cover when the American B52s were dropping ton upon ton of explosive. It’s where they waited when the tanks rumbled through the undergrowth in a futile search for the enemy.

Down in the tunnels were communications rooms, field hospitals, kitchens, and workshops where they turned captured American weaponry and unexploded bombs into the most vicious and effective booby traps.

It all points up the absurdity of the Rambo-style image of the Vietcong as jabbering barbarians being mowed down by the dozen by an American warrior with a bad-ass bandana round his head.

So what’s it like in the tunnels? Helpfully they’ve enlarged some of the entrances so western tourists can get some way down to get a glimpse of the overpoweringly claustrophobic blackness. Some of the entrances have been left as they were – less than a foot square and invisible when covered with a layer of dirt and leaves. The only way in is to slither down feet first, arms straight up. Your shoulders would get stuck otherwise.

In the tunnel it’s impossible to turn around. You have to crawl on hands and knees and even so, the space is only just big enough. Two feet in and the light from the entrance is a pinprick in the blackness. The small flashlight they lent me highlighted the shadows which, if anything, made it seem even more terrifying.

Someone had come down behind me. “What can you see?” She had no torch. The dim beam of light picked out a bat dangling from the roof of the tunnel, stirring, no more than two feet from my face. There was another, also stirring. “Er…rabies?” said my companion, impressively calmly.

But I wanted out, and it’s only when you suddenly want to escape that you realise how oppressive the constricted space really is. The half-panicked scramble back to daylight leaves you with a deep sense of respect for the people that dug and lived in these tunnels.

Topside the shooting range and gift shop gives it a touristy, theme park feel. But down in the tunnels you realise you have come face to face with something serious and important. A visit to Cu Chi is a valuable insight into the insanity that took place here just 50 years ago, and the tenacity of the people who weathered the storm.

Back in Ho Chi Minh City it was hard to relate modern Vietnamese life with the terror and hardship that the people had endured so recently.

That evening we sat on the street, munching barbequed meat while the traffic raced by. Our server, bemused by our presence at his humble stall, was eager to figure out where we were from and what on earth we were doing here. “England! America!” he beamed as we told him our respective nationalities, humbling us yet again with a profound sense of respect for the people that could withstand and then bounce back from such a traumatic experience.

Visiting Cu Chi

You can easily visit Cu Chi on a day trip from Ho Chi Minh City. Tours can be booked anywhere in Pham Ngu Lao, the main backpacker area. Sinh Tourist is a reliable operator. You can also arrange for a private car to drive you directly, expect to pay around 150,000 Vietnam Dong (USD$7) per passenger. Entrance at the Cu Chi complex costs 90,000 VND, once you get inside there are English-speaking guides to show you around (free, but tips are appreciated). Many tours to Vietnam include Cu Chi in their itinerary; check with a tour operator such as Tucan Travel, who organise group adventure tours to Vietnam.