Cu Chi tunnels

Photo: Mark BowyerGuide reveals the camouflaged tunnel entrance

Two sections of tunnels have been opened for tourists - Ben Dinh and Ben Duoc. Ben Duoc is slightly further from Saigon and so the crowds are fewer. It has a more authentic feel and is close by a large memorial and a Viet Cong cemetery. Ben Dinh is about 90 minutes drive from Saigon and Ben Duoc is another 15 minutes on.

The tunnels at both Ben Dinh and Ben Duoc have been widened to accommodate the Western girth - but even crawling through the short stretches set up for tourists can be highly claustrophobic.

Guides at the tunnels have frequently caused both amusement and embarrassment blithely declaring some travellers "too fat" to enter. Vietnamese tend to be less sensitive about weight than Westerners.

The atmosphere at the tunnels resembles that of a bizarre war based theme park - especially at Ben Dinh. Despite the fun park feel, which includes a rifle range where tourists can fire off M16 and AK47 rounds, the  tunnels are an amazing testament to the David and Goliath struggle waged by communist fighters.

Listen to selected audio grabs from the Cu Chi tunnels' old propaganda film.