So, back on topic...
Here's an updated plan of sorts:
From what I've read, the spacing should be fine for the trees as it's more than required for the size of tree I'll be planting. (we're planning 5m spacing.) The soil depth is fine too, but I'll need to check its acidity to make sure it'll support whatever trees we choose to plant.
We're planning to plant a hedge around the perimeter of the site. (It may also go into/thorough the last horse paddock.)
The entrance to the site can be seen to the bottom left corner. Next to that we'll plant a Sweet Chestnut tree. (We really like this tree, so it's more a personal choice than for anything else.)
With this in mind, all things being equal, where on the site would you keep the hives?
Around the trees is one option I've considered. I'm conscious of how close they'd potentially be to the horses. The horses would be secure as we're installing permanent electrified post and rail fencing, so unless they suddenly become acrobats they're not getting out. The hives could also be against/under the tress farthest from the paddocks, not the ones closest.
Near the hedge is the second option I've considered, on the opposite side of the field to the horses. This means the bees will be farther away from the orchard. They'll have whatever food comes from the hedgerow that we're planting. The potential issue with this location is the proximity to the track (in brown) at the bottom of the plan, on which people and horses will be walking. The downside I see with this is that they'll be farther away from where my wife and I will spend a lot of our time, so I won't get to enjoy watching them work.
The other option is more central in the agricultural element of the land (in pale yellow), but then they may be in the way of the hay cutting activity we plan to undertake, and it feels a little exposed just there.
Wherever we end up putting them, I'll be assessing the wind on site and ensuring there's sufficient shelter in place.