An organized transfer from Barth will take you from the hotel to Wendisch Langendorf. You hike a short distance along the Barther Bodden towards Barhöft. It's worth visiting the observation tower here (on your own). From Barhöft the path takes you via Klausdorf to Prohn. Your hike continues from Prohn Stralsund, where you have now reached your milestone. If you don't want to hike that day, you can take the train from Barth yourself Stralsund and have time for a museum visit in Stralsund.
Overnight place: Stralsund