This small museum tells the water-rich history of Chicago, which today has more moveable bridges than any city. The rapid growth of Chicago wouldn’t have been possible without its position on the river, where boats could haul goods in and out on a regular basis, solidifying the Midwestern city’s instrumental role in farming, agriculture and other industries. In addition to a history lesson, museum visitors will get to explore five floors of a historic bridgehouse, and stand on an observation deck beneath the Michigan Avenue Bridge, where you can see the enormous gears that make it mobile. This bridge opens nearly 40 times a year, between April and November, to allow river traffic to pass through, and for $10 you can reserve a spot to see it happen. (Check the museum’s website for upcoming dates.)