UNDERNEATH the rolling Bavarian hillside, Saddam Hussein’s bunker builder gives an insight into the subterranean secrets of the Iraqi leader.

“Listen,” Karl Bernd Esser says, his voice echoing down the narrow tunnels. “I am not a Saddamista, I did not build him tanks or guns — a bunker is not an offensive weapon. The worst you can do with a bunker is bang your head.”

Herr Esser, the 45-year-old civil defence consultant to Saddam Hussein, whose grandmother helped to build one of Adolf Hitler’s bunkers, does, however, have some explaining to do.

The bunker that he codesigned beneath the Baghdad presidential palace could, he says, be smashed only by a nuclear bomb or by 15 Tomahawk cruise missiles landing at the correct oblique angle at exactly the same spot.

What Herr Esser regards as a professional job well done — “It survived the first Gulf War and seems to be bearing up well” — could provide an argument for a nuclear strike. “No, no,” he said. “It’s just that you can only really get Saddam with ground troops. You have to blast open the doors like bank robbers cracking a safe.”

The architect has taken me to a defunct Nato communications bunker in the village of Pfaffenhoven, 25 miles north of Munich, to illustrate the problem. The bunker was built in 1961 but has exactly the same dimensions — 1,800 square metres (19,000sq ft) — and essentially the same layout as Saddam’s presidential bunker.

When the Iraqis first approached him in 1982 to submit an analysis of a planned underground shelter in Baghdad, Herr Esser drew on his knowledge of the Bavarian bunker to provide the necessary guidance. His report, sent to the Iraqi secret police colonel Abdul Moniem Jebara, and later shown to Saddam, makes fascinating reading: a detailed analysis of the need for dust filters, for chemical and nuclear weapon shields, for a redesign of the ventilation channels, for extra decontamination chambers and emergency exits.

“This bunker is far more secure than Saddam’s,” he said, leading me through the frozen gloom of the decontamination chambers. During a nuclear war anyone entering the bunker would have to burn his clothes outside. Then, in underpants, enter a second chamber for a shower. The underpants, would also then be burnt. Visitors would then have to empty their bowels in a special lavatory to purge any contaminated food in their digestive system. The initial three doors are of heavy steel; one is fitted with a time lock.

All this lies under five metres of solid concrete. The tunnels lead deep underground. The 30 inhabitants — a similar number to those housed in Saddam’s bunker — would sleep on bunks in the narrow corridors.

The water filters, the fuel tanks, the communications centre and the generators take up almost all the available living space. “You can see that the stories of Saddam’s luxurious underground existence are overdone, almost certainly propaganda; there’s just no space for real luxury,” Herr Esser said, waving at the piping, resembling the innards of a submarine. “Even if Saddam covered all this up with tapestries, he would still be living a pretty spartan life. The stories have been overdone to drive a wedge between Saddam and his people.”

Since Saddam draws his water supply from a spring about 200 yards from the bunker, it is difficult to see how he could support a swimming pool or even the whirlpool bath that he is said to have in his Baghdad bunker. But if Saddam really has luxury fittings, they could be his undoing, Herr Esser says.

“Wood panelling has to be screwed to the wall — yet the first indirect hit on the top of the bunker would send the screws flying and wood splinters flying in all directions.

“And there would be nothing crazier than marble tiles in the lavatory, as some people claim he now has. The bunker reacts to all impact, and shards from these tiles could cause serious injury.”

Investigations of injuries suffered in Second World War bunkers showed that many were the result of flying debris. Inside the Bavarian bunker, Herr Esser showed us how floors were specially sprung, pipes deliberately mobile and flexible: all to prevent a collapse in the event of a bomb attack. Herr Esser visited the presidential palace in Baghdad in 1984 and advised Saddam that the safest place in his bunker was the lavatory, since it had the smallest surface area. “The translator passed this on to Hussein, who stood motionless and stared at me. There was a deathly hush in the room.” The subject was quickly changed.

Herr Esser became a civil defence consultant after completing an apprenticeship as a bank clerk. In the late 1970s and early 1980s civil defence was still a booming business and he brought with him a family tradition of building underground shelters.

His grandmother had helped to finance the construction of bunkers for the Nazis. One of her projects was the tunnel complex underneath the Obersalzberg, Hitler’s Alpine summer retreat. One could thus argue that the Esser family helped prolong Hitler’s life, just as it is now helping to prolong Saddam’s. The chirpy Bavarian does not see it that way: “Bunkers are neutral - just like airbags.”

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