In the 1850s, before the Civil War, Dubuque was described as “one of the largest and most densely populated [cities] in the state.” The city was “handsomely situated upon a natural terrace,” and it was noted that “this city is more compactly built, and contains a greater portion of fine building than any other place in the state.” 20Dubuque's history of settlement is one of the oldest in Iowa, going back to 1788, when the Frenchman Julien Dubuque crossed over the Mississippi River to begin to mine lead. Mining operations were expanded in the 1830s by the Langworthy brothers and thereafter by others. The first permanent settlement of Dubuque occurred in 1833, and the first platting of the town took place that year and was formalized in 1837. In the mid-1840s the federal government appropriated funds for a harbor improvement. In 1865, a 1,760-foot-long iron-and-stone bridge was completed across the Mississippi River, connecting the city to the Illinois Central Railroad. A few years later, in 1868, the Dubuque and Sioux City Railroad was completed west to the Missouri River. The 1865 railroad bridge was joined in 1887 by the Dubuque High Bridge, a bridge for wagons.

The first section platted for the city lay on a relatively flat field parallel to the river and its plain. This grid was laid out on a north-northwest by south-southeast axis. A large public square was provided at the base of the bluff, on Bluff Street between Sixth and Seventh streets. Later additions to the city adapted all sorts of different “paths” due in part to differences of ownership, the existence of the steep bluff, and other irregularities of the terrain. The steep bluffs and hills of the city encouraged the introduction in 1868 of horsecar service on a number of the streets. Electricity was introduced in 1889, and by 1917 the lines were extended in all directions. Buses were introduced in 1925, and the last of the streetcars ran in 1930. Unusual transportation systems within Dubuque were the two funicular railroads; one of these, the Fenelon Place Railroad, is still in existence.

In 1907 the nationally known city planner Charles Mulford Robinson made a number of City Beautiful proposals for the city. These entailed improving existing streets, providing new parks, and looking to the “improvement of the riverfront” as a public open recreational space. These proposals, as was usually the case, remained on paper. They were followed by a much more thorough and detailed Beaux-Arts city proposal by the Cambridge, Massachusetts, planners John Noland and Justis A. Hartzog. Among the recommendations contained in the 1932–1933 volume, City of Dubuque, Iowa, Regional Plan, was a new civic center to be located between Third Street and Seventh Street, and Locust and Bluff streets. The center of this composition was to be a city hall looking down the axis of Fifth Street to the river. It was to be balanced on the left by a new county courthouse and on the right by a new federal post office and courthouse building, but only the latter was built (1932).

As with other Iowa communities situated on the Mississippi, Dubuque acquired an impressive dam and lock set (No. 11). The dam and lock, located below Eagle Point Park, were started in 1933 and completed in 1937. Like the others on the river, this dam and lock convey a Streamline Moderne image in concrete and steel. In contrast, the housing and central office building constructed by the locks are Colonial Revival in style.

The economic foundations of the community have over the decades been varied. The initial basis was the mining of lead accompanied somewhat later by the city's involvement with steamboats and shipping. Once introduced, the railroad became an important industry. With the influx of central Europeans, breweries assumed importance in the city. By the early 1920s, a wide variety of manufacturing establishments were operating from Dubuque. Another “industry” of the city has been and remains its numerous institutions and schools run by the Catholic church, the Lutheran church, and other groups.

Like other early Iowa communities established on the west bank of the Mississippi River, Dubuque had even before 1850 acquired a number of major buildings, especially churches. The earliest, Saint Raphael's Roman Catholic Church (c. 1835), was a Greek Revival box with a front screen wall, a low-pitched gable roof, and round-arched windows. The uptown Catholic Cathedral (1847) and the church buildings for the Congregationalists and the Centenary Methodists were Greek Revival designs. The Episcopal and the Methodist Episcopal churches were Greek Revival structures modified by entrance towers, spires, pointed-arched windows, and crenellations so that they would read as Gothic. These early church buildings were either drastically enlarged in the following decades or were replaced entirely by new buildings; none of these first churches is still standing today. One of the pre-1860s churches still in use is the First Congregational Church at 255 West Tenth Street. It was designed by a local architect, David Jones, and was built between 1857 and 1860. 21The style was Romanesque, though its telling features of a tower and spire were never built as designed. 22The church has been appreciably modified, both internally and externally, but a close, careful look will reveal the original fabric of the building.

Certainly compared to most American cities, Dubuque has been able to retain a remarkable number of its earlier buildings and monuments. 23Still, there have been major losses, many of which have occurred since 1945. The First Town Clock Building (1864) collapsed in 1872; earlier, in 1858, the five-story (Italianate) Saint Cloud Hotel, “The Largest Building in the Entire West,” burned to the ground. Gone now are some of the city's “grand” houses of the nineteenth century: James Langsworthy's Greek Revival two-story house of 1849; James March's and John Emerson's houses, two impressive examples of the Italianate Villa mode; and F. E. Bissell / R. A. Babbages's Gothic Revival extravaganza of c. 1857. Losses also include the city's first octagon house, the 1857–1866 Federal Customs House and Post Office (designed by Ely S. Parker), and finally the splendid 1894–1895 Richardsonian Romanesque Central High School building (demolished in the 1980s).

The Islamic-style building that housed Catherine Beecher's Dubuque Female Seminary (1853–1859) still stands at the head of Iowa Street, but it was drastically remodeled in 1907, effectively stripping it of its oriental exoticism (it is now the Lady of Lourdes Nursing Home). On the endangered list at the time of writing this guide are the Madison Street Steps (1918), a fantasy of cantilevered and suspended stairs, platforms, and bridges climbing the limestone bluff. The steps are located on Madison Street, just off North Main and Seventeenth streets, but because of the deterioration of the steps they were closed to public use in 1956.

Since the early 1970s Dubuque has plunged into various approaches to historic preservation, contextualism, and urban design. This has led to the restoration of a number of important historic houses, many of them converted into restaurants and bed-and-breakfast hotels. The Egyptian Revival Dubuque County Jail has been rescued and converted into an art gallery. The town's second clock tower now is a centerpiece for the Town Clock Plaza, and Washington Park has been redesigned and now houses a new “Victorian” white gazebo. Though the usual shopping centers have developed to the west (such as Kennedy Mall off US 20), the downtown is still very much alive and vital.