Three massive lake freighters glide simultaneously into three separate locks at the Soo — a rare and dramatic sight captured in vivid Curteich linen color, the bold red hull of one vessel blazing against the bright blue St. Marys River on a summer afternoon in 1941. The Sault Ste. Marie Locks (the "Soo Locks") were the busiest waterway in the world by tonnage at this period, connecting Lake Superior to the lower Great Lakes and funneling iron ore, coal, and grain across the industrial heartland of America. On June 17, 1941 — just months before Pearl Harbor — two travelers named Cub and Helen dashed off a breezy note from the observation deck to friends back in Port Huron, joking that if a woman named "Dar" drove them crazy, they should send her to Detroit.