LAST summer, on the Atlantic coast of France, Charlemagne was introduced to a fine beach game: building big sand-walls near the shoreline in the face of a rising tide.

• 去年夏天，法国大西洋沿岸，一种有趣的沙滩游戏加入了查理曼大帝元素：涨潮时在海岸线上建多重沙滩长城。