Ottawa was incorporated in 1866 and in 1867 voted to become a city of the second class under the guidelines established by the State of Kansas. During the same time frame, a bridge company was formed, and constructed a suspension bridge across the Marais des Cygnes River at Main Street, purchased by the City in 1874. City Hall was constructed at the corner of Fourth & Walnut in 1911 and remained at that location until August 1996 when it moved to 101 S. Hickory.