Stalag XXB (Marienburg) was situated in and around modern MALBORK, Poland.
The camp was very large, with many sites and centres - not at all like the "Great Escape" style camps.
Some POWs were billeted with local famers to work on the farms, because the local young men were all away at War; My father worked in the farms. Later he worked in sugar beet factories.
In Feb 1945 the camp was evacuated in a dreadful forced march to the West - to avoid the oncoming Russian Army. I have a book (and my father's diary) describing the 10 week march through the Polish winter. My father met US forces at Brunswick and was was repatriated in May 1945.
With typical Army humour he was then put in charge of German prisoners in a UK PoW camp !!
Did Herbert T Evans survive the War ? You can request his Army records (if you are next of kin); they may contain a debrief that he would have performed on returning to UK. They may also contain other details of his capture and POW status.
See here
http://www.nationalarchives.gov.uk/records/research-guides/prisoners-war-1939-1953.htmfor information on what is held at National Archives in Kew.
I attach a photo taken (illegally I assume), near Stalag XXA Torun (Thorn) Poland, in 1942 showing British POWs at work.
