Nicollet Tower: See Two Other States
Sisseton, South Dakota
Frenchman Joseph Nicollet spent two years making the first accurate map (1841) of the area between the Mississippi and the Missouri Rivers. The idea of an observation tower overlooking that vast area is a good one, but it wound up in Sisseton -- where everything is somewhat flat -- because the campaign to build it was spearheaded by a Sisseton banker.
From the top of the 75 foot tower visitors can see the ground below in South Dakota, and reportedly a little bit of North Dakota and Minnesota as well. The tower's Interpretive Center displays a replica of Nicollet's "mother map."