S20·E13 Crocodile City / Spanish Galleons / World's Largest Windmill / Cement

This magazine edition includes four segments: a look at Lamanai (Crocodile City), built by the Maya of Belize between 400 and 300 BC, as it was being excavated by David Pendergast of the Royal Ontario Museum, assisted by other specialists and a work-force of direct descendants of the Maya; Spanish Galleons: A look at the recent discovery and exploration of Spanish treasure ships wrecked off the coast of Texas four centuries ago, and techniques used in identifying encrusted objects; World's Largest Windmill: Students and teachers of a Danish Folk School have built a windmill 75 meters high that produces 2,000 kilowatts of electricity, and Cement: A look at the properties of cement.