If you are considering walking this route yourself, please see my disclaimer. You may also like to see these notes about the maps and GPX files.
Immediately before the road crossed the Grand Union Canal, I went down some steps on the right and turned sharply left along the towpath (so immediately going under the road). I followed the canal for about one and a half miles, going under just one other bridge. Just past the Cow Roast Marina I reached a lock and another bridge, where I left the canal and turned left along a lane that immediately turned right, almost parallel to the canal.
The Grand Union Canal
The Grand Union Canal
The Grand Union Canal
The Grand Union Canal
The Grand Union Canal
The lock at Cow Roast
After one or two hundred yards I took a footpath on the left. This went across a field and over a footbridge across the main West Coast railway line. Beyond another field the path brought me to a path T-junction where I turned right, then soon turned left at a second such T-junction. This brought me to Norcott Court Farm, where I went a few yards left to the entrance of the farmyard then turned right to reach a gate. The path then went diagonally across a large meadow, rising very gently uphill as it crossed to the far corner. The path then followed the right edge of a large field to a corner, where it went over a stile and continued across a sloping sheep pasture, aiming for the far corner.
The start of the path to Norcott Court Farm
The path to Norcott Court Farm after I turned right at a path T-junction
The path to Norcott Court Farm after I turned left at a path T-junction
The start of the path from Norcott Court Farm to Tom's Hill
View left towards the footbridge taking the Ridgeway over the A41
The path from Norcott Court Farm to Tom's Hill (it follows the field edge to the field corner, then crosses the green field to its far corner)
The path from Norcott Court Farm to Tom's Hill
The path from Norcott Court Farm to Tom's Hill