Infographic The ‘Impossible’ Obstacles of Monte Cassino a Breakdown of Tanks, Defences and the Looming Abbey

The hill itself was 520m tall, had a 46m high structure atop it, and the building boasted 3m-thick walls.

It was surrounded by ravines, and the Allies faced appalling winter weather.

From the bottom of the mountain, “the monastery was almost vertically above you,” notes Matthew Parker. “A trained climber with all the modern equipment in daylight would find it a difficult climb to get up there. Imagine if you're in the dark and you’re wearing rubbish army boots and you're under fire. It's just almost impossible how difficult it was for those young men.”

The German forces had also burst a number of dams in the area, and the Rapido river had in turn burst its banks as a result. This made it impossible for tanks to navigate the area easily.

We can see the just how commanding the German position was from these comparisons:

• The Abbey was situated on a hill which was around 1.75 times the height of the London Shard and Eiffel Tower.
• Mortars could easily bombard oncoming attackers from a height equal to almost 120 times that of a double-decker bus.
• MG42s were located throughout the ascent, suppressing soldiers from battlements at an equivalent elevation to 7-10 storey buildings.

As the battle progressed, the Allies had to take the town and abbey street by street, advancing slowly through each building. Sometimes, Allied and Nazi troops occupied different rooms of the same house, and progress would take weeks.

Monte Cassino’s abbey hill was dotted with German machine gun instalments, mortar cannons and snipers that continually suppressed the oncoming soldiers from above.

“The Germans had plenty of time to work out all of the possible approaches of the Allied troops to their positions. And there was something like 24,000 mines laid,” notes Parker.

“There’s barbed wire. There are machine guns on fixed lines. So, they can press a button and anyone coming through this obvious approach just gets shot.”

One hill at Monte Cassino was nicknamed the $1,000,000 Dollar Hill, because the Allies spent $1,000,000 worth of shells trying to capture it. To put this in context, that would be about $17.2 million today.