And the first of the ordeals was the tunnel itself. Once again I hear our uneasy cries drowned by the huge thunder of the train passing overhead. Once again I see the circle of unwelcoming daylight at the end doubled by its reflection in the great lake that collected inside the tunnel after rain. Once again I feel the awkward twist of my body as I turn to edge sideways along the narrow causeway left at the edge of the lake, and simultaneously lean away from the glistening, dripping wetness of the brickwork. Once again I feel the dank touch of the walls on my hair and shoulder, and brush at the foul exudations they've left. Once again I try to wipe the dark-green slime off my hands.