Arundel Castle and Arundel Park
This circular walk takes you through the parkland and countryside surrounding this restored medieval castle in West Sussex. The walk starts near the castle and picks up the Monarch's Way long distance walking trail to take you into Arundel park. You'll pass Swanbourne Lake and follow footpaths through woodland and grassland to the River Arun. The route then follows a lovely riverside footpath back towards the castle. You'll pass the splendid Arundel Wetland Centre where you can look out for a wide variety of wildlife including water voles and rare geese.
The castle itself is well worth visiting with lovely gardens and a fascinating history, though there is a fee for entry to the grounds.
The Slindon Estate is located just a few miles to the west of the castle so you could continue your walking in the area by visiting this 1400 hectare estate.
If you follow the Monarch's Way east you will soon come to Angmering Park Estate Woods. There's miles of good cycling and walking trails to try here.
There's also the Amberley to Arundel Walk which takes you along a lovely waterside footpath next to the River Arun.