We were only back two days and then we saw a cow in the garden! how could this possibly be when the whole land is fenced off now?! by the time we'd got our boots on it had disappeared and we couldn't find it anywhere. But the next day there were two more! this time I ran after them when they ran off, and I followed them through the forest to the south-west corner of the land where it turns out there's no fence across the river!
It's a difficult area to fence because the banks are a metre or so high and there's nothing very low to attach fencing wire to. We decided it needed to be fenced off asap, so I got to work on it straight away. First I put a normal four-wire fence across joining the existing fences, and then to fill in the metre or so of gap in the river below this new section, I connected vertical pieces of wire attached to four sacks of rocks sitting on the river bed. The best ones are made with wire mesh, but we only had enough for two, so another is plastic mesh with some wire to support it and one is a large chunk of metal pipe.
It was a really horrible job! it was a cold overcast day and I had to wade into the mud and cold water which filled up my boots. Every time I needed to attach wire to the east side, I had to walk about 50 metres up stream to get to a point where I could get up the bank, then go back and attach the barbed wire all with soaking trousers, socks and boots!