Big Digs: Amazing Underground Constructions

K-Gr 5–This fascinating history of underground construction marvels takes ­readers from earliest times to the present in a chronological journey through gargantuan human feats of engineering. The colloquial tone is spare and humorous, with an eye on innovation through the ages. Beginning with the “Tunnel of Contents,” chapters include the ancient (1100–300 BCE) walls of rock and caves in Cornwall, now the United Kingdom. “Over the years, it has been pillaged by collectors and nosy people,” which means there’s not much left to discern its use. Best guesses are the low-ceilinged, narrow tunnels may have been burial sites or grain storage. Surely, the rocks were dragged from distant quarries, which testifies to incredibly hard work in ancient times. Works include the Gadara (Jordan) Aqueducts in the 1st century; the 12th century Dover Castle; Spiral and Tijuana Narco Tunnels; the Seoul Subway; the Chunnel Tunnel between England and France; and even the White House Bunker in Washington, D.C. Most unusual is the Svalbard Global Seed Vault, which preserves agricultural biodiversity in case of global wars and is built into the rock to withstand floods, earthquakes, volcanic eruptions, or other disasters. Located on a remote Arctic island, the temperature is kept at zero degrees ­Fahrenheit to avoid contaminating seed samples. Many other incredible big digs with superb illustrations will galvanize students and inspire pre-engineering aficionados.