George McCaskill previously operated a farm, store and grist mill in Summersville, Missouri with his older brother James. But in 1890, he moved on to his own ventures when he purchased property along Rocky Creek with partner Joshua Sholar. The pair had the intentions of running a mill at this location near Winona, Missouri in Shannon County. Those plans may have been thwarted by a severe flood that struck the area, the same flooding that also struck the small crude mill of Charles Klepzig at Alley Spring, putting that man out of business.
In 1893, George McCaskill sold his share of Rocky Creek to Sholar and purchased the Alley Spring property from Klepzig.
Alley Spring was first homesteaded by James Tackett in 1848. A mill was later built in 1873 by John Daugherty and his father-in-law, Stephen Barksdale. Like most mills, a community grew around the operations and the town at the spring became known as Barksdale Spring, and the mill known as Daugherty-Barksdale Mill. The mill was a small dam below the spring branch and a simple water wheel and crude shed over the millstones.
Daugherty’s father served in the Confederate army under General Price in Missouri. He was wounded at the Battle of Wilson’s Creek and died from the wounds three days later. Young John had married Mary V. Barksdale in 1860 and like his father, served in the Confederate army. Daugherty was captured at one time and suffered some sort of disability during his campaigns. He was released from captivity on pardon, as long as he agreed to not return to service of the Confederacy. He returned to Shannon County and in 1873, he and Barksdale built the mill and ran it until approximately 1881.
John Daugherty moved to Salem, Missouri in 1881 after selling the mill to a German immigrant, Charles Klepzig. Klepzig opened a post office at the mill and in his application put in for either “Shannon” or “Alley”. Alley was chosen, apparently for the name of a prominent farmer in the area and the name Alley Spring Mill stuck.
The aforementioned sale from Klepzig to George McCaskill in 1893 put the younger McCaskill in business on his own, and he immediately began to update and enlarge the milling operations at Alley Spring. That mill structure is the one that still stands at the site.
Tragedy struck the McCaskill family just as the new Alley Spring Mill was being completed. A tornado tore through the area and Lizzie, the sister to the two McCaskill brothers perished, along with her infant child. George would soon move to Eminence to be closer to the Alley Spring operations, and also served as treasurer of Shannon County for a time.
The new Alley Spring Mill used a turbine, rather than a water wheel, and implemented steel rollers rather than a stone grist to grind the grain. McCaskill sold the mill site in 1897, and Alley Spring Mill then passed through several owners until shutting down as an operating mill in 1924.
The Missouri State Park system purchased the mill and 427 acres of land that same year. The old general store, blacksmith shop and spring house were removed. In 1927 a flood destroyed much of the dam and head gate, and footbridges. Federal work programs in the 1930s completed repairs and development of the park through a Civilian Conservation Corp (CCC) project. The mill became part of the Ozarks National Scenic Riverways in 1971.