Yes. Why?
It's not that straightforward.
The plan in the title deeds is an OS map with a scale of 1:1250. The difference between where we say the boundary lies and where our neighbours say the boundary lies is approximately 0.5 metres. (Yes, that sounds stupid, but there is probably a reason, which I'll explain in a minute.) On the plan that would equate to 0.4mm, and - bearing in mind the explicit warning about scaling from the plan - that's far too small to be useful.
There are physical features present. There is a tall hedge on the line which we say is the boundary, and there is a fence on the line which our neighbours say is the boundary, and they are 0.5 metres apart.
The thing is, we built the fence in 2003, and we deliberately built it a little way back from the hedge (which was the only physical evidence of a boundary when we moved in, in 1994) for reasons which our neighbours now dispute. Their argument is that we built the fence on the line of the pre-existing boundary, which is not the line of the hedge. Their argument is completely groundless - for instance they argue that we built the fence to line up with the fences either side of us, but there are no fences either side of us, just the hedge. But they're being so aggressive about it, we're concerned that it will end up in court. We expect we will win in court, but there's no guarantee that a court will award costs, so it could end up costing us money to defend our position. My approach is to try to pile up as much evidence as I can, to try to persuade the court that the neighbours' claims are entirely without merit, and hopefully that way we'll be awarded costs.
Incidentally, insofar as I can ascribe a rational motive to our neighbours' actions, I think the issue is really about ownership of the hedge. We've recently extended our house at the back, so our garden is smaller than it used to be, and the hedge - which is about 6-7 metres tall - now looms larger in our sight and blocks out a lot more light. We'd very much like to trim it. But our neighbours don't want us to - "You touch that hedge and I'll see you in court" - because they seem to have concerns over their privacy. It is clear from the title deeds of both our house and theirs, and we all agree, that responsibility for whatever structure might lie on the boundary - hedge, wall, fence, whatever - is ours.So if the hedge is the boundary then we have the right, indeed the obligation, to maintain it. But if the fence is the boundary then the hedge is on their land and we don't have the right to trim it. I think that's what it's all about.