My parents have bought my 72 mod 1300 beetle back 12 years after I owned it and have found major cracks under both wheel arches at front of both wheels. Has anyone ever come across this, been able to repair and know why this happens?

Someone has had a go of repairing and made a mess of it.

My good mate had a similar thing happen to his late model beemer, it was professionally repaired and braced so it wouldn't happen again. Unsure why yours has done that though, did the crack start due to rust?

if its a strut front end rust where strut , or I would call it just rust .

It's a torsion bar front end. And no rust? Beam was cut and turned 12 years ago to lower the front end.

Thats metal fatigue. So sort of vibration or stress in that area has fatigued it.

Any evidence in the spare wheel well of a hit?

I've seen one that was hit in the front end do that many years after the prang.
I would bet small tears started when they straightened it and spread through vibration.

Same thing might have happened with yours.

Yep, I agree with Joel

Repair would involve drilling out the crack tips to relieve the stress (and prevent further propagation) and then weld the whole crack back up

Just be cautious to not start a fire with the trim etc on the other side (IE: remove).

You could just drill out teh crack tips to prevent it spreading for the time being.

Copy. Will be up at the parents this weekend so will have a closer look to see if it has had some previouse damage. And I will tell the old man about possibly drilling out the ends of the cracks.

Thanks for the feed back.

could you anneal that area to relieve stress and soften the metal?