Alley Spring sits at the bottom of a wooded bowl twelve miles west of Eminence, and the deep blue pool with the bright red mill rising behind it is one of the signature images of the Missouri Ozarks. The spring pushes out around 81 million gallons of cold water a day, enough to drive the mill's turbine year-round before it closed in the 1920s.
The mill itself is a three-storey wooden building with a corrugated tin roof, painted a strong oxide red. It has been preserved rather than restored — you can walk through the ground floor and see some of the original milling equipment, but it has the air of an industrial workshop that closed last week, not a polished museum.
A short loop trail circles the spring pool and gives the postcard view of the mill from the far side. The picnic area beside the spring is one of the best in the park; the swimming hole on the Jacks Fork just downstream is one of the most popular.