barrier free parkway and stairway shortcut in a park on the asterstein in koblenz

walkway lawn asphalt grass yard sidewalk backyard lane road garden estate tree flooring property tarmac suburb plant koblenz germany 2021: fort asterstein prussian located east rhine origin name one city area military fortress built 1820s 1920s systems remains memorial ruin shape still plants cover roofs barrier parkway stairway shortcut park