Lock 42

Lock 42

Photo by Bud and Dell Cline

Locks 41 and 42 are located at the north end of a calm stretch of Potomac River aptly named “Big Slackwater.” Depending on which direction a Canal boat was headed, locks 41 and 42 either dropped boats to the river or returned boats to their normal 16 feet above river level. The locks were originally constructed of blue-gray limestone, but many sections have been replaced with concrete. Learn more.

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Visiting the C&O Canal

We know that to preserve something, you need to experience it, so we are proud to provide support to the C&O National Historical Park as their official philanthropic partner.

Please visit the National Park Service website for the following information:

For more information and nearby places to stay or grab a bite to eat, please visit our local tourism partners:

Photo by Bud and Dell Cline

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