By the mid-1870s, Mason City had emerged as the principal city of north central Iowa. The site for the city was selected, as Andreas noted in 1875, for its “advantage of timber, building stone and good water,” and the town has also been “favored with excellent railroad facilities.” 15There is nothing remarkable about Mason City's original plat of 1854. The north-south, east-west grid was set out a short distance from the confluence of Lime Creek and Willow Creek. Subsequent additions to the grid in the nineteenth century continued the same basic alignment. The first mill was erected in 1854 on Lime Creek, and others followed shortly. The city's importance as a rail center began in 1869 with the completion of the McGregor and Mississippi Railroad line (now part of the Milwaukee Railroad). Other lines were added in the 1879s, 1880s, and as late as 1909.

The abundance of fine clay for brick and tile encouraged the establishment of several major industries. These were joined by enterprises that used the nearby lime deposit for the manufacture of cement. Other important elements of the economy, historically and now, are food processing, meat packing, and transportation and distribution.

Architecturally, little remains of the early decades after the city was founded. 16The stone Canon house of 1866 off route 1 represents a late example of a simple one-and-a-half-story Greek Revival house. In the downtown area there are the remains (usually at the second or third floors only) of commercial blocks of the years 1880 through 1900. The Parker Opera House (1883) at 21 North Federal announces its links to the Italianate style quite strongly in its upper two stories. A number of the residential streets of the city still contain many examples of the Queen Anne and Colonial Revival. One of the most interesting of these houses is the Colonial Revival Patton house of 1902 (at 623 North Adams Avenue). The designer of the house seems to have started with the theme of a single two-story volumetric box and then with seeming delight added porches, bays, and wall dormers.

The City Beautiful movement with its characteristic reliance on the Beaux-Arts Classical is exhibited in several public buildings from the turn of the century and later. These include the (former) Mason City Carnegie Library of 1903–1904 (Patton and Miller, 208 East State Street), the former Post Office Building of 1907 (James Knox Taylor, now the city hall, 19 South Delaware Avenue), and an imaginative pergola entrance to the Public Comfort Station in the city's original Central Park of 1855 (Hansen and Waggoner, 1925, 2 North Federal Street).

What has put Mason City on the national scene is its active participation in the development of Prairie architecture and planning. Frank Lloyd Wright was brought to the community in 1907–1909 to design the City Bank and its accompanying Park Inn ( NO205). In 1911, Walter Burley Griffin and Marion Mahoney Griffin entered the scene and planned the idyllic suburban community of Rock Crest-Rock Glen. Previous to this, Wright's associate William Drummond, who had seen to the completion of Wright's bank and hotel, had designed a house in the area. Others of the Prairie group, such as Barry Byrne, realized buildings, or, like Purcell and Elmslie, proposed them. These architects were joined by an intriguing local Prairie school practitioner, Einar O. Broaten.

As always seems to be the case with a situation such as this, a handful of individuals were responsible for introducing the Prairie mode into Mason City and for sponsoring the Rock Crest-Rock Glen development. All of these people were involved in business or the practice of law in the community. They included two lawyers, James Blythe and J. E. Markley, and the development contractor, Joshua Melson. Griffin himself characterized the potential of the site and the approach that should be taken to it: “Rock Crest and Rock Glen occupy two sides of a valley which Willow Creek has carved out of the rocks within three blocks of the central square.… The endless fascinating possibilities for domestic architecture with the unexpected variations of view, soil and ruggedness, luxuriance, prominence and seclusion, need only the due attitude of appreciation to work themselves out.” 17

The approach that Griffin took to the suburban design of the valley was in principle identical to the one he had used earlier in laying out Trier Center in Winnetka, Illinois (1911–1912). This consisted of grouping dwellings close to the street, leaving a parklike open space in the center, a space which would be a common for all of the inhabitants of the place. Griffin took full advantage of all of this to produce his own version of a Picturesque English garden, almost a twentieth-century version of one of Capability Brown's mid-eighteenth-century English gardens.

Architecturally, Griffin felt this was a real opportunity—the presence of the tile and cement industry in Mason City could further his introduction of the use of reinforced concrete, both in structure and in aesthetic appeal. He was also enamored of the visual prominence of outcrops of limestone in the area, and this “natural” material entered into all of his designs. Griffin's departure for Australia, where he had won the design competition for the new capital, Canberra, meant that many of his projected dwellings were either never carried out or were modified when built. Griffin brought in Barry Byrne, another of the young Prairie architects, who left his mark through several of the Rock Crest and Rock Glen houses.

In addition to the Prairie houses around Rock Crest and Rock Glen, there are a remarkable number of houses in town which can be related to the style. These include, of course, Wright's 1908 Stockman house ( NO218); the Yelland house of 1912–1914, attributed to William Drummond; plus a good number of houses (spec and otherwise) probably designed by the local architects Einar O. Broaten and J. H. Jeffers. If indeed Broaten designed such houses as the Critelli house (1909, NO210) and several other tentatively attributed to him, then the architect should be placed within the front ranks of the Prairie movement.