The tallest single-step lock in North America and second-tallest in the world, the Pinopolis Dam at the south end of Lake Moultrie  separates the impounded lake from the Cooper River. If you’re in a boat or kayak, it’s a whopping 75-foot, half-hour drop from the lake to the 1940s-era Tailrace Canal, a short run on which takes you to the river.
Generally, nonpowered craft are not allowed in the lock. But for a guided kayak tour including a jaunt through the lock, contact Blackwater Adventures (843/761-1850, www.blackwateradventure.com ). The trip, which runs in the neighborhood of $50, includes a two-mile leg down the Cooper River.