Cat proofing fences - ideas?

Cats are kind of like burglars. If a burglar wants in, he'll get in. If a cat wants out, he'll get out. The fact that they are inside cats does give you an advantage because they might not be so curious. I'd say a high wood fence is going to be your best deterrant from them escaping but no guarantee.

Hi Arella the fences are mostly pretty high, but cats can climb fences, there's plenty of this sort of idea around, I'm just looking for recommendations/experiences:

Looks like a good high fence. It's been my experience a cat can climb most anything, the little stinkers. But that fence hanging over the top like that might deter them. I hope you find a solution.

I recall that, after moving into my current place, although the Colourbond fences were high, the bloody cat dug his way out underneath them. I had to go along the length of the back fence and concrete in the gap between fence and ground, and a bit either side, to make it too difficult / annoying to dig out!

And then the trees grew - and he could climb them to get over the fence.

Current cat is too fat / lazy / arthritic to get over the fence, but I still worry that other cats, you are not quite so f/l/a, can get into the yard from outside.

The way the yard and fences work I'm pretty happy cats won't dig out. Yay. We're only talking about having the cats outside while we're home so they'll be semi-supervised and hopefully we'll spot Colditz behaviour.