Based on the 13th Century travels of King John, The 3 Castles Path connects Windsor Castle with the Great Hall in Winchester (all that remains of that castles) via the remains of Odiham Castle. 

The Route follows a continuous chain of public right's of way with a few additional permitted paths through crown estate land. The routes winds its way through parkland, forests and heaths, as well as beside streams and canals and through picturesque villages.

The route has its own Website, Facebook Page and a detailed guide book available:

If you are wanting to add to your collection of Wisconsin Rail to Trails consider The 400 State Trail! It gets it’s name from the Chicago-Northwestern railroad passenger train that used to travel the 400 miles between Chicago and Minneapolis/St.Paul in 400 minutes.
It was officially opened in 1993 and is 22 miles of friendly, well marked and well maintained trail. It travels through Reedsburg, La Valle, Wonewoc, Union Center and Elroy. Each small town is anywhere from 4 to 8 miles apart with trailheads that have parking, water and bathrooms.