Somewhere nice to stop halfway please?

I have never found anywhere decent on the M3/A303 until well south of Exeter....which would make for a very late lunch! All the nice towns are a fairly long detour.
Probably explains why Fleet services are always so busy.

You could try Avebury?

There is a website, something like 'whats half way' .com or .co.uk. May give you some ideas.

Solstice Services near Amesbury? Not wonderful but there should be a choice of eateries - just watch out for Russians!

I gues it depends on timing but you could try coming off on the A3. There is a little cafe and picnic spot immediately on your left with a walk in the woods or if you want to be posher RHS Wisley is a bit further. You will have to rejoin the A3 and hook back or take a couple of B roads to get back on the M25.

I guess Marlborough’s too much of a detour. They do very good cake!

How about Cobbs. It is a farm shop with a great restaurant near Hungerford. Or is that out of your way?

I will look these all up as I am not familiar with that part of the country at all!
Thank you