Noise coming from the rear when turning corner as about 20mph

[Smunns]

i have had this noise for a bit now and have had a look under it and can't find anything wrong under the rear end but when i am driving it at around 20 mph and turn a corner i have a clunk from the rear []

 

[Buddy]

Not much info to go on but if it is a thump then personally I would check for anything loose in the cabin and storage areas, is the seat belt able to hit the side under cornering? You don't say whether it is when you turn right or left but that is also an indicator of where a problem may be, hatch counterweights are known for a trunk clunk as the Americans call it or maybe something adrift inside the hatch, if you suspect it is underneath maybe the tailpipes are catching the trim if mounts have gone soft? could be a support bracket with a loose bolt, ( there are two bars which go fore and aft at an angle under the rear just inboard of the wheels and of course the under trays which end just by the front end of the engine ) other wise it will be necessary to check suspension mounts but you also don't mention if there is any untoward behaviour in the cornering.