Park at Warnham Nature Reserve and then walk out to the road and head left on the pavement. Walk past the mill and cross over and the route starts just the other side of the bridge.
Very flat walk, the main paths are well signposted and these are level gravel tracks. Venture away from the paths and there's muddy woodland trails.
If you stick to the main paths then there's not too many places where there's accessible water. There are lots of smaller mud trails and in various places these lead down to the river but will be slippery in wetter weather. Shallower banks and smaller streams are further along the walk.
Poo bins at the start of the route, in the car park and dotted around throughout.
The nature reserve where you park is very nice but no dogs allowed. Close to Horsham town centre and shops a short drive away.
As the name suggests the route here follows the river and whilst my walk was just under 3.5km, you can walk much further if you wish.
It's a popular place so great for socialising dogs, and nice and flat throughout so very easy.
The paths are well signposted, so follow those and it's a straight forward there-and-back route once you get as far as you want to go. If you venture along the muddy paths then it's a more varied walk through woodlands and with more access to the actual river, but first time visitors (like me today!) may get a little lost and you can end up in the golf course quite easily at the start of the route, but it's generally not too far to head back and retrace your steps.