David Gilbert has spent the past 40 years exploring 19th century mill sites, raceways, and old canals along the Potomac and Shenandoah rivers and their many tributaries. His fascination with these historic places began when he worked as a canoe instructor and whitewater rafting guide for River & Trail Outfitters in Knoxville, Maryland. Gilbert has written several books about Harpers Ferry, including A Walker’s Guide to Harpers Ferry (1983); Waterpower, Mills, Factories, Machines and Floods at Harpers Ferry, 1762-1991 (1999); and The Burton Drawings at Harpers Ferry, The Emergence of 19th Century Drafting Practice at the U.S. Armories (2021). He has also contributed to several National Park Service publications, where he worked for 11 years as a writer and editor. One of his fondest memories is of a family canal boat trip on the Llangollen Canal on the border of England and Wales.