Kauai Museum is the island's only full-fledged museum. They're easy to find, located on Rice Street with a hard-to-miss orchid tent right near their main steps.
Inside, you'll find several different themes. The first one, on the lower level, features relics from the days that kings and queens ruled Hawaii. You'll be able to find little cups, rugs, paintings, books, and furniture from this time.
Upstairs you'll find exhibits detailing the suguar plantations. Tools, paintings, and clothing are on exhibit.
Please note that the museum changes its themes, so it might be different when you finally get there. One thing won't change...it will always be engaging and interesting!
The Kauai Museum also has a great little bookshop so that you can buy something to remember your visit.
Pros: Lots of interesting history!