In truth there were varying ammounts and types of trenches, which by the end of the war, looked like a maze.
The order of trenches generally ran as follows
The Front Line (Front Trench) was generally lightly garrisoned and only occupied at 'stand to' at dawn and dusk.
Between 70 and 100 yards behind this line was the support trench which was occupied by the garrison when the front trench was bombarded
Then between 300 and 500 yards behind that trench was located the third reserve trench, where the reserve troops would amass id the front line had been captured.
Behind these three trenches was loctaed another trench system, generally X number of kilometers from the front. This trench system would be occupied in times of retreat
It has been calculated that a general Infantryman's time was divided as follows:
* 15% front line
* 10% support line
* 30% reserve line
* 20% rest
* 25% other (hospital, travelling, leave, training courses, etc.)
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