These locks – operated by the Army Corps of Engineers – are popular among visitors and locals in Seattle. The locks allow boats to pass between Puget Sound and the Lake Washington ship canal, offering a live demonstration of Seattle's maritime lifestyle (many have compared the locks to a miniature version of the Panama Canal). After you've watched a couple barges pass by, head to the south side of the locks where fish ladders help salmon migrate during the summer months; if you're lucky, you might catch a glimpse of a sea lion looking for a quick bite to eat. The fish can be seen up close from special viewing windows. The Chittenden Locks are also home to the Carl English Botanical Gardens, which feature a variety of unique plants and beautiful views.

Many visitors suggested taking one of the free tours offered to learn more about the history of the locks. A few reviewers were disappointed that the visitor center was closed the day they stopped by. If that's something you want to explore, make sure you check the hours ahead of time. 

The locks are available to visit daily from 7 a.m. to 9 p.m. and are located in northwest Seattle's Ballard district. Free one-hour tours run from March 1 to Nov. 30. A visitor center is open daily May through September from 10 a.m. to 6 p.m. From October through April, the center is not open Tuesday and Wednesday and closes at 4 p.m. the rest of the week. There is no entry fee for any of the attractions here. The locks can be found north of downtown and about 5 miles west of the University of Washington. You can reach the locks by driving or taking bus routes nos. 29 or 44. For more information, check out the Hiram M. Chittenden Locks website.