Pipestone National Monument
This place was celebrated in a classic painting by the artist Catlin and showed the quarrying of pipestone - which unfortunately was then given the name catlinite - ridiculous even though we like Catlin's work.
The important thing about this site is that it is still a place where Indians come to collect the soft claystone for creating pipes and other pieces of art. There is usually a Native artisan in residence carving within the visitor center. A very good set of displays to explore the geologic story of the land and the Indian's connection with it. Outside there are the active pits and a paved trail that leads you through the prairie, past an ancient quartzite rockface, along a stream and up to a beautiful waterfalls. It is a cool retreat on a hot summer day.
In a land of farms and prairies, it is nice to find a place with a few trees for shade and natural cooling, especially on a day when the temperature hovered around 93F.