This photo, showing a group of POWs in a swimming pool, is an excellent highlighter for showing the ingenuity of the soldiers. Like all the sporting and theatre facilities, this swimming pool was created from scratch by Allied prisoners of war with little, if any, supplies and help from the German guards.
The photo may have been taken at either Stalag XX A in Poland or Stalag 383 in Germany, the latter of which held an Anzac Sports Day on April 25th 1943 and later 1944 (Anzac Day). The Anzac Day events were open to either Australasian or any soldiers who saw active service in 1914-1918 (and of course were imprisoned in Germany in 1943 or 1944) with 20 events being held in total.
If anyone is interested here are the recorded results for the main event in 1944 - the 100 yard Australasian Sprint Championship, in which one runner represented each Australian State and each New Zealand Island:
1st - [Unknown] Leggett - representing New South Wales (time 10.6 secs)
2nd - R. Byrne - representing New Zealand North Island (time unknown)
3rd - E. Hull - representing New Zealand South Island (time unknown)