Having lived in Missouri nearly all of my life, there is no excuse for me having never visited 5 very famous Missouri places and now is confession time.
If you love beautiful things, Illinois has some options and none are better than what amounts to a humongous rock garden that you can hike through if you're brave.
If you love the lake life, but don't want to spend an arm and a leg on the pastime, a Missouri place was just named the most affordable lakeside town in America.