Recommendations for climbing plants

Roses? May be too tall but they make a lovely hedge.

I might go for pyracantha for the middle lawn trellis and ivy along the wall with a notice saying 'here be spiders' that should stop the kids sitting along the wall too, lol.

Shysal

The pyracantha has thorns so might be the best for the job, especially if it reaches crotch height!

Pyracantha and Euonymus look nice and hardy, I've never managed to grow clematis in that garden, I think the winds just batter them too much. Can't beat a north sea breeze for flattening your plants, lol.

I'll check out honeysuckle and hydrangea to see if they can survive here.

I have more trellis if needed to create a bit of an obstacle course for them, I've had three people drop stuff off today and only one used the path and thats because he had to park further down the road! I wouldn't mind, but its only a matter of walking an extra 4yards at most.

Thinking more about this, I think Pyrocantha would be a good deterrant. It is evergreen and has white flowers in early summer followed by yellow, orange or red berries.

Climbing hydrangea? You could train it over the trellis? A Montana clematis would cover quickly but can be a bit of a thug, although they are useful.

Try an evergreen honeysuckle or clematis.

It has insignificant flowers, but Euonymus can be grown up a trellis or be self-supporting. I use them in both ways. They are easy to keep in shape and evergreen. There are various colours but I like the cream edged ones which grow faster than the yellow edged ones.
I hope you find something you like. I have the same problem with the postman crossing my lawn, perhaps I will copy your idea.