This plaque dedicated to the 'super-human' efforts of Louis-Arsène Bigot (1810–53) bringing the springs of Grainval to Fécamp involved what, exactly? Ah, he dug tunnels into the chalk and flint cliffs in order to give water to the people of Fécamp. Amazing for a twenty-six-year-old illiterate guy. And the town now (occasionally) does visits to the tunnels. Pity we couldn't make it, as this sounds fascinating.