burg pfalzgrafenstein castle in upper middle rhine valley unesco world heritage site at kaub, rhineland palatinate, germany

tower landmark castle building vacation fortification waterway hill town mountain water terrain burg pfalzgrafenstein upper middle rhine valley unesco world heritage site kaub rhineland palatinate germany beautiful historic customs station set small island falkenau river gorge rhineland-palatinate rocks narrow shipping toll picturesque towers roofs turrets bastion bow cannons forest blue sky clouds summer day nature natural environment water medieval white fortress history famous west western central German Europe tourist attraction destination tourism