Originally Posted by Blumie

So I don't remember how I came up with this route, but I've done it numerous times and have always enjoyed it. It sounds complicated, but I've never had any problem following the route and not getting lost. It certainly sounds like a bit of a challenge if you've never done it before; I'll try to be as detailed as possible.

The main road running adjacent to Terminal 5 is called Western Perimeter Road. When exiting Terminal 5, i just take a left and follow the terminal roadway the short distance until it ends, and then take a left on Western Perimeter Road. From the Sofitel it looks a little more complex, so either ask or take the lift back to Terminal 5 and start from there.

On Western Perimeter Road, you want to stay on the side of the airport. This is the least interesting part of the run. Western Perimeter Road ends at Southern Perimeter Road. Here, cross Southern Perimeter Road (there's a cross walk, or whatever you call them in the UK) and turn right on Southern Perimeter Road. You will shortly come to a roundabout, and take the first exit onto Stanwell Moor Road. You then want to take the first right onto Horton Road, the first street that you come to, which requires you to cross over Stanwell Moor Road (there's no cross walk, but I've had no difficultly dodging traffic). Horton Road leads you into the neighborhood of Stanwell Moor, so your run gets a little more interesting,

The pub in Stanwell More is called The Anchor. When you see The Anchor on your left, turn right to stay on Horton Road. Shortly thereafter you'll come to a fork with Spout Lane on your right, but keep to the left to stay on Horton Road.

Believe it or not, that's all been the easy part. Here it gets a little more complicated. If you stay on Horton Road, you'll end at what I think is the M25. But off to your right, just before you reach the M25, is a not-very-well maintained foot path. (On google maps, it looks like that might be called Leylands Lane.) Go on the foot path and you'll shortly see an underpass under one of the M25 exit ramps, followed by a bridge over the M25. This is what you need to take to stay on Horton Road. Follow the underpass and the bridge over the M25 and follow the path back to the continuation of Horton Road. Cross over Horton Road, and take a left on Horton Road. This area is mostly industrial and businesses serving the airport, so is not the most attractive, but I find it far superior to the road directly adjacent to the airport.

Follow Horton Road until you come to a roundabout with a pub called The Golden Cross in front of you. Take this right on Poyle Road, and continue on Poyle Road until you're forced right on Bath Road (I think there's a pub at this point called the Punch Bowl). Follow Bath Road until it ends at the highway -- I think you're back at Stanwell Moor Road, albeit a stretch very close to the Sofitel and Terminal 5. At this point, turn around and follow the same directions back to where you started. I think this is all just under 10k.

So it sounds complicated, but again I've done it without difficulty. Map it out on google to get more familiar with it, then give it a shot!