Christy Park, according to the city website, is comprised of 16.1 acres of park land, established in 1910.  There are no official boundaries listed on that website, so I can only assume that Christy Park and Joseph Leisure Parks are one in the same.  There is actually a band of parks that start at Kingshighway and Christy and head south and east toward the River Des Peres, following the Great Rivers Greenway Trail starting near Christy and Holly Hills Boulevards.