A bit of searching has suggested that the path behind Edinburgh airport runway was rideable once upon a time.
Having had a gander tonight (always trying to avoid riding the same old boring paths in Edinburgh) the section west of the railway line looks like it once was a reasonable path, but is presently pretty overgrown, and although I rode for a bit, I gave up eventually. I had hoped to link up with the road bridge you can see over the Almond.
Can anyone confirm if once upon a time it was possible to go all the way through to Kirkliston? I suspect that if it wasn’t summer (i.e. if the nettles and bushes weren’t so overgrown), and if enough people rode/walked it, it would be a nice wee CX/MTB link. Unfortunately I didn’t get as far as the Gogar Burn before giving up, and turning round. Worth persevering? Is there a usable path on the north side of the river which might be better?