It was hardly the sort of “welcome to Lithgow” they were expecting, confronted by heavily armed men, some in balaclavas, looming out of the wintry gloom at road blocks to demand identification before allowing them to proceed.

Once the initial sense of impending doom settled there was a simple explanation. It was an unannounced Army anti terrorism exercise based on the State Mine Museum and State Mine Gully area and realism was the order of the day.

This correspondent was stopped three times at roadblocks within half a kilometre or so with a demand to produce a driver's licence or some other form of identification. They also wanted to know the purpose of our venturing along that road.

The soldiers probably didn't have any legal authority to make such a demand but they were polite and you don't argue with someone toting a Steyr assault rifle. Even if you know all the weaponry on display was hopefully loaded with blanks.

The troops themselves didn't look too comfortable; freak weather descended on the region at the same time as their exercise, giving them the experience of defending the nation in near freezing temperatures, rain, sleet and snow.

The exercise meant that the Mine Museum was off limits to we mere civilians for the weekend.