Darkest Depths and Other Underground Megastructures Ian Graham
The tallest, the biggest, the longest and the deepest - all these amazing megastructures are revealed in this title in detail...with some incredible facts and stats to absorb! This is a brand-new series for older readers. With amazing centre gatefold, it is packed with up-to-date details and fascinating facts and stats. It features fantastic photos of the world's greatest megastructures.