Helena was initially founded in the downtown section. On July 14, 1864 four miners, dubbed the "Four Georgians" (though only one was from Georgia), discovered gold in a creekbed along what today is Helena's downtown main street, Last Chance Gulch. This sparked a cultural and building boom that lasted 30 years and Helena became the state capital. The city grew from south to north along Last Chance Gulch, its main street, and hence the evolution of architectural styles can be traced. At the southern end the road is narrow with small log and stone buildings and at the northern end the road is wider and has large stonework homes. Few major downtown buildings were built in the years immediately after the Panic of 1893, which among other problems, caused the closing of the local silver mines. This resulted in downtown Helena having a sharp division in its older and newer sections. Most of the newer buildings were small, had a single function, and had a false front. At the time of the initial 1972 NRHP nomination, some of the significant buildings that still stood from that early time were: the Electric and Power Blocks, Helena Athletic Association, Auerbach Buildings, Merchants Hotel (later Monticello Apartments), Atlas Block, Diamond Block, the Wheat Building (Merchants National Bank Building) and the Lewis and Clark County Courthouse. A major fire in 1928 affected the area, destroying many original buildings, including the Granite, Bailey, Gold, and New York Store blocks. Additional buildings in the downtown section were damaged or destroyed in the 1935 Helena earthquake. Helena's early commercial district was located along State, Edwards, and Broadway Streets, but fires destroyed much of this area in 1869, 1872, and 1874. Much of what was built afterwards was built in the Western Commercial style, with splendid brickwork and simple lines. The Beaux Arts Parchen Drug Building, Colwell Building, and the Penn-Block Bristol Hotel were French Renaissance. The Denver Block and Sands Brothers Dry Goods were Romanesque Revival. By the mid-1880s at least 18 architectural firms had been established in Helena or called in from back East. Several of these architects were part of or influenced by the Chicago school of architecture. This influence is seen in the Atlas Building, Securities Building, Power Block, and the Lewis and Clark County Courthouse. The most significant changes to the area occurred in the early 1970s, when a major urban renewal project demolished about 240 buildings within the original Helena Historic District—61 of them were of historical significance. Most of these buildings were commercial in nature and were concentrated in the southeastern section of the district. The architectural and historical building survey initiated prior to the project was later deemed incomplete, and the decision to destroy many buildings of "indisputable historic and architectural significance" created significant controversy in the community. Urban renewal was viewed by many locals as a "disaster" equal to the 1935 earthquake, as many "insipid" new buildings were put on in the place of demolished historic structures. However, many historically significant buildings are still standing today including the Atlas block, the Securities building, the Placer Hotel, the Iron Front hotel and the Montana Club. The Helena Historic District (HHD) is a federally designated historic district in Helena, Montana, United States. Since its establishment in 1972, the HHD has had boundary adjustments in 1990 and 1993. The original 1972 designation was composed of two unconnected sections known as "Downtown" and "West Residential.