In reply to Tommyads:
Right, life will be easier now I´ ve dragged mine out and looked at it! It isn´ t flag pole it is a fishing pole known as a whip. Mine is 6m and they are called travel whips as they pack down to 58cm.
Here´ s the Decathlon 5m one so you know what to look for, no doubt they do other sizes.
https://www.decathlon.co.uk/lakeside-1-travel-500-id_8324376.html
Expect to lose the top couple of segments, they are hell of a flexible!