Mason City is a city in and the county seat of Cerro Gordo County, Iowa, United States. The population was 27,338 in the 2020 census. Mason City is known for its musical and masonry heritage, as well as being home to a significant collection of Prairie School style architecture. Along with nearby Clear Lake, the city forms a regional commercial, industrial, and cultural hub for north-central Iowa.
The Mason City Micropolitan Statistical Area that includes all of Cerro Gordo and Worth counties is located at the transportation junction between Interstate 35 and the Avenue of the Saints. The first White settlers arrived in the area in 1853, and they were John Long, Joseph Hewitt, and George Brentner, who hailed from LaSalle, Illinois. Long was a member of a Free Masonic Order, and they initially named the dense wood thicket as Masonic Grove. The next year, in 1854, more settlers involved in Free Masonic groups arrived, and platted a town, first known as and Masonville. Coincidentally, the name Masonville was proposed by John Long to honor his son, Mason, who died en route to then Shibboleth. In 1854, John McMillin opened the first store, and Dr. Silas Card opened the first medical practice in the area. Ultimately, in 1855 the name was changed to Mason City to differentiate from another Masonville in Delaware County.
Until 1855, Mason City was without local county government, and Cerro Gordo County (named for the Battle of Cerro Gordo during the contemporaneous Mexican–American War) was attached to the Floyd County government and commission. In August 1855, Cerro Gordo County citizens voted to organize their county government, and three commissioners were appointed to decide on the county-seat. The commission had selected Mason City as its preferred county seat. In December 1856, the Iowa General Assembly voted to relocate the seat of government closer to Clear Lake, then known as Livonia. In April 1858, county citizens prempted that change and voted against relocating the seat from Mason City, where it has remained ever since.
Early growth: 1850-1900
The United States Post Office Department started service to the town in 1857. In 1870, Mason City, Iowa was officially incorporated as a town with Darius B. Mason as the first mayor. Historically, the largest industry in the city was brick and tile manufacturing, limestone quarrying, and cement production. The land in the vicinity of Mason City, is rich in clay and limestone deposits that allowed the growth of a large masonry-based industry. Much of the success of the Mason City Brick and Tile industry was achieved under the leadership of O.T. Denison, who was a proprietor in three of the many brick yards, including the largest, the Mason City Brick and Tile Works. Under his direction, the company came to own most of the brick works in town, the North Iowa Brick and Tile Works being an exception. Until about 1934, Iowa used more drain tile than any other area of equal size in the world, and Mason City was the center of this manufacturing.<gallery mode="nolines" widths="200">
File:Stratified clays in clay pit of Mason City.jpg|Stratified clays in clay pit located in Mason City, IA. Circa 1895.
File:Mason city.jpg|Downtown Mason City, IA. Circa 1883.
File:Clay-pit-of-the-mason-city-brick-and-tile-company.jpg|Clay pit of the Mason City Brick-and-Tile Co. Circa 1890.
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The city was first connected to the railroad in 1869 by the Dakota Branch of the St. Paul and Milwaukee Railroad. It was later connected to the rest of the state with a line built by the St. Louis and St. Paul Railroad, which shipped large amounts of coal mined in southern Iowa to the northern side of the state to fuel emerging heavy industries, such as brick and tile in the vicinity. In 1896, the Mason City and Clear Lake Railway was originally founded as a rail transit between the cities. Since 1937, the railway has operated only as a freight route and is currently known as the Iowa Traction Railway. The Iowa Traction Railway is known as the last electric shortline interurban railway in the nation.
thumb|The former Parker's Mill along Willow Creek. Built in 1870 by H.G. Parker. Now the site of the [[Rock Crest–Rock Glen Historic District|Rock Glen-Rock Crest housing development.]]
Era of sustained growth: 1900-1970
At the turn of the 20th century, in 1907, renowned architect Frank Lloyd Wright visited Mason City to complete design work for a prominent businessman. Mason City was fortunate to have Wright and several of his associates, including Walter Burley Griffin, Marion Mahony Griffin, and Barry Byrne, leave behind several notable examples of their distinctive prairie school architectural style. Burley Griffin and Mahony Griffin later gained fame for designing the plans for the new capital city of Australia, Canberra. Among Wright's contributions to the community are the first Prairie School-designed home in Iowa, the Frank Lloyd Wright Stockman House constructed in 1908; the Park Inn Hotel, the sole surviving hotel designed by Wright, built in 1910; and the City National Bank building, completed concurrently with the hotel. The Rock Crest-Rock Glen area witnessed the development of the largest collection of Prairie School-style designed homes on a unified site. The First National Bank was robbed by John Dillinger and his gang on March 13, 1934. They escaped with $52,000 despite the fact the bank actually had more than $300,000 on hand that day.
thumb|Mason City Postcard, 1950.
In 1954 a new breed of horse was introduced in Mason City. The Pony of the Americas (POA) grew to be one of the most popular breeds of horses in the country. Gentle and easy to train the POAs were especially suited for young people. This special breed of horse can be seen along with a variety of horses at the many equine events held at the North Iowa Events Center in Mason City throughout the year. In the 1950s and 1960s, the addition of the sugar beet industry and the pork packing industry helped Mason City to become the largest urban center between Des Moines and Minneapolis-St. Paul at the time.
In 1959, early rock and roll stars Buddy Holly, Ritchie Valens and The Big Bopper (J.P. Richardson) took off from Mason City Muncipal Airport after a concert at the Surf Ballroom in nearby Clear Lake, Iowa, en route to Fargo, N.D. The plane crashed a few miles west of the airport in an historic event later referred to as the Day the Music Died. Holly, Valens, Richardson and pilot Roger Peterson all died in the accident.
Modern era: 1970-present
During the 1970s, the originally dominant brick and tile industry began to decline, prompting Mason City to diversify its economy. On February 23, 1977, a very rare February tornado occurred in Mason City. Further challenges emerged in the 1980s with the Farm Crisis, which severely impacted the Upper Midwest agricultural economy and the economic prospects of nearby farms. This led to a state-wide downturn and migration out of the area. Mason City was the site of the 1993 Iowa Murders, and later was the site of a high-profile disappearance investigation, following the abduction of KIMT reporter and news-anchor, Jodi Huisentruit in 1995. Since the mid-1990s, Mason City has focused on revitalizing its downtown area, constructed the Southbridge Mall, a hockey arena, and developed a regional retail economy centered on the west side of town nearing Clear Lake. Since the turn of the 21st century, Mason City has experienced steady community development, and has continued the revitalization of its downtown district and the architecturally significant Park Inn Hotel and First National Bank. In 2008, Mason City experienced extreme flooding where the Winnebago River reached its highest crest recorded in history at 18.72 feet which overtopped the levee system.
Geography
According to the United States Census Bureau, the city has a total area of , of which is land and is water. Mason City is located in the north-central region of Iowa, and is 120 miles north of the state capital of Des Moines, and 140 miles south of the twin cities of Minneapolis and Saint Paul. The city lies along the Winnebago River, formerly called Lime Creek and Willow Creek, the main outflow of Clear Lake, which is 8 miles to the west. Other creeks within city limits include Camlus Creek, Chelsea Creek, and Ideal Creek. There is also a slough on the northeastern side of the city called Buffalo Slough bordered by Plymouth Road. The vicinity is located within the Winnebago-Shell Rock-Cedar-Iowa River watershed, which later joins the larger Mississippi River system downstream.
thumb|245x245px|Mason City landscape, [[Ethanol fuel|Ethanol plant in distance.]]
The geology of Mason City and other surrounding areas in Cerro Gordo County include deposits of clay, limestone, dolomite, and sandstone. These sedimentary rocks fueled an important economic sector of longstanding quarrying, brick, and cement production. Much of the remaining land within and near city-limits was once tallgrass prairies, but has now been developed as rich farmland. This region of the Upper Midwest is known as the Prairie Pothole region includes flat landscapes and glacial lakes.
Climate
Mason City has a warm-summer humid continental climate (Köppen: Dfb), bordering closely on the hot-summer variant. This area has four distinct seasons, with humid, warm summers and cold, snowy winters.