Sterling silver Citizens Military Training Camp sweetheart ring. What is the CMTC? Citizen’s Military Training Camp – Continuation of the “Plattsburgh Movement” of WW1 into WW2 Citizens’ Military Training Camps (CMTC) were military training programs of the United States. Held annually each summer during the years 1921 to 1940, the CMTC camps differed from National Guard and Reserves training in that the program allowed male citizens to obtain basic military training without an obligation to call-up for active duty (online research). Inside hole measures 7/8″ across. I believe it is a size 8. Nice condition,overall wear and patina. Not cleaned.