Minn. Const. art. XIV, § 2

There is hereby created a trunk highway system which shall be constructed, improved and maintained as public highways by the state. The highways shall extend as nearly as possible along the routes number 1 through 70 described in the constitutional amendment adopted November 2, 1920, and the routes described in any act of the legislature which has made or hereafter makes a route a part of the trunk highway system.

The legislature may add by law new routes to the trunk highway system. The trunk highway system may not exceed 12,200 miles in extent, except the legislature may add trunk highways in excess of the mileage limitation as necessary or expedient to take advantage of any federal aid made available by the United States to the state of Minnesota.

Any route added by the legislature to the trunk highway system may be relocated or removed from the system as provided by law. The definite location of trunk highways numbered 1 through 70 may be relocated as provided by law but no relocation shall cause a deviation from the starting points or terminals nor cause any deviation from the various villages and cities through which the routes are to pass under the constitutional amendment adopted November 2, 1920. The location of routes may be determined by boards, officers or tribunals in the manner prescribed by law.