Interesting (longish) article on how the wooden piles that support Venice were done and a bit on their survival. Also interested on how the Venetians protected the forests that supplied them.
www.bbc.co.uk

Mud, water and wood: The system that kept a 1604-year-old city afloat
Most modern structures are built to last 50 years or so, but ingenious ancient engineering has kept this watery city afloat for more than 1,600 years – using only wood.
