I wonder if an Invisible Fence may have been easier in that ugly terrain? Although trenching may not have been any easier.
Easier yeah, but doesn't keep out other dogs. Also does't work on power failures and dead batteries, plus they have to wear those pokey collars all the time.
Still not sure the trenching would have been easier on that ugly terrain. Anyways, I loved my Invisible Fence. Dog only had to wear the collar when outside. We kept it on the coat rack. It was a small collar. Same collar for toy breeds and cats (not sure how it would work on a cat??). So pretty small.
You have a problem with dogs coming into your yard? Like larger dogs attacking your smaller dogs??
Our neighbours about 500m away have the invisible fencing, in places they had to just run it over the surface of the rock, still ok but a bit more susceptible to damage. Our property was mostly pretty easy to do with real fence, I also didn't really stick to the property line and went where it was easier.
We have had problems with people at the cottage next to us though, a family owns it and one of the siblings lets their dogs run free (and they drink and fight and play obnoxious music etc.) so we have had their dogs on our deck a few times. Another "lady" who doesn't even live on our point runs her dogs down the road beside her SUV, one got into a fight with our other neighbours dog last fall. There's also the occasional bear.
Mostly it's not a problem, but I feel a bit safer with a real fence.