interior of restructured bergfried tower, today used as observation tower, of ruined castle burg zavelstein, black forest.

staircase castle wooden stairs tower zavelstein steps ground high angle view 12th century abyss access ancient architecture bad teinach-zavelstein bergfried black forest bottom building castle ruin depth europe germany high angle high angle view historic history illuminated landmark light medieval observation observation tower old rebuilt reconstructed ruin ruined castle stone structure tall teinach teinach valley tourism tourist view wall wooden stairs