sankt goar, germany - 08 04 2022: festung rheinfels, castle ruin

river reservoir waterway hill town transport mountain coast village highway valley landscape infrastructure bridge sankt goar germany 2022: waterfront area terrace rhine sank goarshausen northern small lorelei passage loreley rock written historically versions found still modern days narrow mittelrheintal dangerous summer drought sandbanks reef rocks visible water level middle unesco world heritage castles ruins festung rheinfels castle ruin