Produced between 1933 and 1934, 'Dominance of the City', is Coltman’s masterpiece. The huge painting is a mural triptych, consisting of three separate and distinct panels depicting specific areas of Cleveland. The largest part, the middle segment, displays a bridge rising over the Cuyahoga River near the Flats. The left portion depicts the Ohio Bell building, and the right panel portrays St. Theodosius Church in the Tremont neighborhood.
'Dominance of the City' can be found at the Cleveland Public Library Main Branch on the 3rd Floor in the Cleveland Digital Public Library.