Contrary to popular belief, neither the North Vietnamese Army nor Viet Cong guerrillas could match the U.S. forces toe-to-toe during the Vietnam War — either in skill or of firepower.

What they could do is hamper the Americans' ability to pursue them in a retreat.

One of the ways they did that was by using creative methods to rig booby traps to injure or kill U.S. troops.

U.S. Troops nicknamed "tunnel rats" cleared VC and NVA tunnels for enemy soldiers and booby traps.

They were often marked by the Viet Cong using broken bushes, palm leaves, or certain alignments of sticks, such as a rectangle or tripod. The retreating Vietnamese would fashion traps from crude spikes, grenades, wires, and even memorabilia.

1. Punji Sticks

These are traps made with sharpened bamboo stakes, often smeared with urine, feces, or another substance that would cause infection in the victim. The VC would dig a hole and put the sticks in the bottom, then cover it with a thin frame. The victim would put his foot through the cover and fall on the spikes below.

A more insidious trap featured spears pointed downward so victims would be injured only when they tried to pull out of the trap.

2. Snake Pits

Yes, this is exactly what it sounds like. Viet Cong guerrillas would often carried Bamboo Pit Vipers in their packs to (hopefully) kill anyone who searches through them. They would also tie the deadly snakes to bamboo and hide them throughout their tunnel complexes. When the Bamboo was released, so was the snake – right onto the enemy.

Sweet dreams.

The snakes were nicknamed "three-step snakes," because three steps was all you could make before the venom kills you. U.S. "tunnel rats" had to be specially trained to navigate and disarm these traps.

3. Grenade-In-A-Can

Two cans were mounted on trees along either side of a path. The safety pins on the grenades are removed and the explosives are put into cans, which hold down the striker levers. The tripwire was then tied to each grenade. When the wire was tripped, the grenades were pulled out of the cans to detonate instantly. This could also be done with one can and a stake.

4. Flag Bombs

The NVA and VC loved to fly flags and they knew U.S. troops loved to capture enemy flags. So when they were forced to leave a base or location, they often rigged the flags with an explosive of some kind, so when US troops started to take down the flag, it would set off the charge.

In fact, any attempt to move the pole or flag set off the booby trap. This is similar to a "keepsake, lose hand" trap, where the NVA would intentionally rig anything a U.S. troop would consider a war trophy with an explosive.

5. Cartridge Trap

This trap was an awful one because it was very difficult to detect. A cartridge – a round of ammunition – would be set into a piece of bamboo and lowered into a shallow hole in the ground. At the bottom of the bamboo was a board and a nail.

The regular weight of someone walking on the cartridge would drive the nail into the primer, turning the nail into a firing pin and firing the bullet upward through the unsuspecting victim's foot.

6. Bamboo Whip

Another sharpened bamboo trap, the whip consisted of spikes over a long bamboo pole. The pole was pulled back into an arc using a catch attached to a tripwire. When the wire is tripped, the catch gives out and sent foot-long spikes into a trooper's chest at a hundred miles an hour.

7. The Mace

Another tripwire trap, the Mace may have been the worst of all Vietnam War booby traps. Once the wire was triggered, a 24-inch metal or wooden ball with spikes welded onto it, weighing 40 pounds or more, would swing down from a tree, sending anyone in its path straight to Valhalla.

8. Tiger Traps

A tiger trap was similar to the mace, in that a tripwire would undo the catch on a rope. Only instead of a swinging ball, the death from above took the form of an man-sized plank weighted with bricks and full of barbed metal spikes quickly falling to earth on someone's forehead.