Birds Nests In The Terrace Walls Resembles The Pine Trees In Park Guell, Spain

park guell guell terrace wall antoni gaudi world heritage site gaudi wall stone structure walkway ancient nature viaduct environment tourist attraction roadway unesco architecture spain travel tourism catalonia landmark pine tree scenery tree natural grow bird nest attraction carmel hill pine park destination plant resemble closeup medieval terrace building la salut vacation old no people barcelona tourist public facade nobody