Anti Landing Trench, Castlemartin

Marianne pressed her palms against the cold trench wall and felt the vibration of ships passing above. The bay dropped into black water beyond the sand, but the trench cut through the living rock like a knife. She had mapped the coast for weeks, searching for the hidden line that separated the old world from the new. When she marked the trench on her chart, every other coastline vanished, leaving only the sharp edge where the sea stopped obeying its own rules.