Route advice from Hampshire to Fort William

Aim to take a break every couple of hours and consider an overnight stop en route. I would also suggest you don’t take the route up the west side of Loch Lomond, but instead head for Callander and then onwards to your destination 

Have done this recently from Bedfordshire, sounds like you're staying at Bunree.

I can recommend a stop at Troutbeck Head just off M6 on A66 to break up the journey, it is still 220 miles from there.....

A82 on Northern part of Loch Lomond is very tight & probably not recommended for towing, I'm sure other caravanners will be along to advise....

Maybe use M73/M80/A84/A85

Make sure you visit Neptune's Staircase, good day out & amazing engineering.

Enjoy the stunning scenery.

Personally I would prefer the eastern route up the country, it’s only about 20 miles further. For me when we were towing I would want two stops, it’s is over 500 miles. So A34, M40, A43, M1, northern link round Leicester onto A46 and then A1 at Newark. Overnight at Clumber Park (just off A1) 187 miles. Then A1 A66, M6, A74 to Strathclyde Country park just south of Glasgow 240 miles. Leaving a nice 116 miles the final day, going via Callander, M74, M73, M80, M9, A84, A85, A82. Rather than the west side of Loch Lomond, which is only a few miles shorter.

Winchester to Fort William is a minimum of 520 miles and although you are used to driving long distances solo there is a big difference for a novice with a caravan in tow. It can prove very tiring if not stressful. As Kasspa and Extugger have said, the northern end of Loch Lomond is not a good road for many miles. It is quite narrow and twisty in many places and the many logging lorry drivers don't slow down for anyone !! I have done this route but I've been towing for 40 years. The route suggested by Kasspa is by far better but longer. Consequently I'd have at least two overnight stops. 

My overall average speed when towing is 44 mph so it would take me, as an experienced tower, 14 hours plus refreshment stops every couple of hours. Poolesbrook CaMC site near Staveley, Chesterfield may be a good site for an overnight, if you can get a booking. It is very close to the M1. That is about 180 miles from Winchester.

I'd then go onto the M18 to the A1M. The M1 around Leeds is a horrible road (concrete) and it's also longer. I'd then try to book a site somewhere somewhere well south of Edinburgh. Berwick on Tweed CaMC site (Berwick Seaview) would be about 210 miles from Staveley, again if you can get a booking. That would leave about 190 miles to get to Fort William. The total would be in the region of 270 / 280 miles. Longer but, in my opinion, far easier and a bit more relaxed.

Hope this helps. Don't be too ambitious for your first long tow and remember, you have to drive back again 

I definitely agree about avoiding the A82 alongside Loch Lomond. When we had a caravan we would stop for the night in Staffordshire (just shy of 300mls from home), Moffat for the second night (a bit less than 200mls) and could do Oban or Fort William in about 4 hours on the third day.

If it was our choice it would be Newbury/Oxford to M40 north, then M42 to the M5/6 and straight onto the M74 north. I'd guess a stop over in the Midlands/Lakes would be on the cards and maybe somewhere near Stirling for the last bit.

Warwick is good for the M40/M42

Kendal is very handy for the M6.

Depends how long you want to drive for.

I think if you're new to this part of the uk two or three stops would ease the journey.

Should have said in post above, a total of 570 / 580 miles not 270 / 280 !!!

Agree with Brue on route. 220miles a day spacing would give me Moss House Farm site near Wigan (junction 27 of M6)  for first night and another 220 miles to Keltie Bridge or Blair Drummond in the Stirling area for second night, then 100 miles on third day to Fort William .

I've done this drive with a caravan quite a few times i would take the road through calender a few other  member's have just mentioned. It's longer but a better road .hope fully i will be taking this road again in September.also Annandale water is a good service area i found it caravan friendly.enjoy the drive the scenery is awesome.

Much good advice there for you to mull over, but don't forget it is all supposed to be a Holiday  so don't go at it like a Hamilton or Vettel