I have a long winding 45m access path, including a zigzag that would be the envy of any Tour de France cyclist, to achieve height gain between trees and not to disturb their valued roots.

I would like to have lighting on the path, and have identified some post lights that might fit the bill, both separate lights and plug and play 'kit systems'.

I would prefer to use LED lights.

I would like them to have PIR detectors that would switch them on at either end - but that may not be feasible.

I would prefer to use low voltage SELV, and to power the transformer within the house, but I am not clear what cable might be required for this - the consensus on the thread 24V DC or 110V AC or 240V AC in the garden? seems to favour 240v since this curtails the size of cable. I have put in ducting, in which I oculd run pond cable as suggested by JSH in another thread here:

 

OTOH 240v seems to present more complex installation issues, which I would be most happy to avoid.

I look forward to reading your learned opinions.

As in that other thread, to make the wiring easy, and a safe DIY job, I'd use SELV outdoors, using a tough, waterproof cable like H07RN-F or H05RN-F/3182P, run inside 25mm conduit.  The big advantage, apart from safety, is that it's a lot easier to wire up this cable than it would be to wire up SWA, and you would need SWA if you wanted to run the lights on 230V AC.

 

You don't need a lot of power to adequately light a drive using LEDs, a couple of watts per light is enough, so the current can be quite low, which means a modest size of cable to ensure the voltage drop isn't too great. 

 

If you use a dusk light sensor to turn the power on to the SELV system (to minimise day time vampire loss) then you could fit SELV PIR switches to control the lights.  If you wanted sensors both ends, then you could run 3 core cable instead of two core, with one core being the SELV feed to the far end PIR, one being the switched SELV power and the third being the return.  You may have to hunt around for SELV PIR switches, I've made quite a few for our outside lights, using modules, but I haven't looked to see what's available as ready made units.  There are lots of LED outside lights available, in various styles, and it's worth looking at pond and patio lights, as they tend to be SELV.