I asked the Lindenwood park supervisor about this marker. Lindenwood Park was created in 1924 and the GAR (Grand Army of the Republic) organizations were created by union civil war veterans. John F. Reynolds was a general killed in the Gettysburg. PA in July 1863 and never ever visited the Minnesota or the Dakota territory. It is speculated that some of the veterans that served under him settled in the Red River Valley.
Why the exactly location of this marker has been lost. There is a statue of the general located in Island Park.
Permission has been granted for placement of this cache. I asked that all caching be done during DAYLIGHT during the camping season (May-September).
The cache is not at the marker, so there is no need to disturb anything in that area. Enjoy this area of the park and you might see deer or wild turkeys.
BYOP