Colo. Rev. Stat. § 3-1-116
The exclusive jurisdiction for all purposes, except such as are in sections 3-1-116 to 3-1-118 expressly reserved, over and all that tract, piece or parcel of land known as Fort Lewis, in the state of Colorado, known and described as follows, to wit: Beginning at a post marked "O.M.U.S.M.R.", on the northern boundary of the Southern Ute Indian reservation, due south nine thousand two hundred and sixty-nine feet from the southwest corner of section thirty-five, township thirty-five north, of range eleven west, of the New Mexican principal meridian; thence south eighty-eight degrees, twenty minutes west along said Ute line four miles; thence due north five miles; thence due east five miles; thence due north one mile; thence due east five miles; thence due south five miles, three thousand seven hundred and sixty-six feet to said Ute line; thence south eighty-eight degrees, twenty-five minutes west along said Ute line, three miles; thence south eighty-eight degrees twenty minutes west along said Ute line, three miles, to the place of beginning, excepting therefrom all sections, and parts of same, and all lands and parts of same, now filed or entered, the titles to which have been, or may be perfected by the present claimants, their heirs and assigns, all bearings from the true meridian, be and hereby is ceded, granted, transferred, conferred, and confirmed unto the United States of America, for and during the time the United States shall remain the owner thereof; but, nevertheless, jurisdiction to serve the civil process of state, county, and municipal courts and tribunals, within said tract, and also to serve and execute thereon process in criminal cases, by state, county, and municipal officers, in respect of offenses, misdemeanors, crimes, and felonies committed outside of said tract, is reserved to the state of Colorado.
C.R.S. § 3-1-116
For establishment of Fort Lewis college on this property, see part 1 of article 52 of title 23.