Research Tools

The Clear Lake Public Library History Room and the Clear Lake Historical Socienty offer a wealth of research tools for anyone interested in exploring the town’s rich past. Visitors can access local newspapers, historic photographs, genealogical records, maps, and city directories that trace the community’s development over time. The collection also includes oral histories, yearbooks, and archival materials from local families, businesses, and organizations. Whether you’re researching your ancestry, restoring a historic property, or simply curious about Clear Lake’s heritage, the History Room and Historical Society provide the resources and guidance to help bring your story to life.

The Clear Lake History Room is located inside the Clear Lake Public Library. It is open to the public on Monday and Tuesday from 1 p.m. to 3 p.m., Thursday and Friday from 1p.m. to 5 p.m.  For more information or assistance, please contact the library at 641-357-6133 or email clplhistoryroom@gmail.com

The Historical Socienty is located at 801 1st Ave South.  It is open to the public from May 1 to Sept 30, Tuesday-Saturday 10am-2pm, from October 1- April 30, Friday and Saturday 10am-2pm.  For more information or assistance, please contact 641-430-7729 or email CLIowahistory@gmail.com.

Research Tips and Sources

What are you researching?

Information on a Person or Business

• Published directories at the Library such as Polk Directory and Telephone books
• Plat Maps and Rural Directories,
• Clear Lake newspapers 1860-1950 issues on-line and 1950-2016 on microfilm at the Library
• Mason City and area newspapers on-line through Ancestry.com and paid sites such as Newspapers.com and News
• Search the Clear Lake Scrap book for mentions using the Scrap Book index
• Search the Clear Lake obituary clipping using the Obituaries Index
• Use the search function on our website for mention of people or businesses
• Review the history book and publication catalog for information

Genealogy Research

• Ancestry.com genealogy website available with free access through the Library public use computers
• Iowa GenWeb site for Cerro Gordo County.
• Family Search  for Cerro Gordo County
• State Historical Society of Iowa
• State of Iowa State Library
• Iowa Graves Survey-WPA 1930’s registration survey
• Cemetery Graves-Find a Grave website

 Information on a House or Building

• Cerro Gordo County Assessor-Beacon Search website using the address of the property.  Use the history tab to view prior year building photos
• Cerro Gordo County Auditor– website for land transfers. Transfers from 1860s to 1950s digitized handwritten, 1950 onward Iowa Land Record site digital records
• Sanborn maps of Clear Lake at Hub
• Use the Street Name and Number conversion map at the Library to translate pre 1949 street names and addresses to the current listing.  Streets and numbers were changed in 1949
• Review the property abstract for your home of business, research other abstracts at the Auditor office
• Search newspapers for mentions of a property, building or building owner’s name

Looking for a Photo- Note if you want to use a photo for commercial purpose please contact us

• Search our photo archives on-line or at the Library or Historical Society
• Search our Photo Gallery Page

The completion of comprehensive catalog of the holdings of the Library History Room and Historical Society is an element of the digitization program.  The Collection Catalog will contain a listing of the physical and digital materials that make up the collections of the Public Library History Room and the Historical Society. These materials are available for research only at the History Room or Historical Society. 

The first list of telephone subscribers in Clear Lake was issued in 1896. It was a listing of 20 subscribers; users simply told the operator who they wanted to call. After the Clear Lake Telephone Company was incorporated in 1908, telephone books were published, but the operators still had to connect the calls.

The 1909 and 1911 Clear Lake Phone Books at the History Room list subscribers, phone number and street name only, no addresses for the City subscribers.  For subscribers outside the city, they were grouped into party lines with up to 8 subscribers with long/short ring codes for each party.  After you answered your ring code, the operator would connect you with the caller. However, everyone else on your party line could listen in; you had to be careful what you said.

The Mason City phone books were published by Northwestern Bell and included Clear Lake and some surrounding communities.  The Mason City Library History Room has phone books that include Clear Lake from 1917 onward.

Were your relatives in Clear Lake in 1909 or 1911 and did they have a phone?  Check out these 1909 or 1911 phone books.  Follow the link below for the digitized phone book collection

1911 Clear Lake Phone Book

High School Yearbooks (also called “Annuals”) are the “Cultural Time Capsules” of local society focusing on who they were at a pivotal moment in their lives.

Perhaps the most unique feature of a yearbook is that it is an interactive document. The autograph pages transform a mass-produced book into a unique personal artifact. These handwritten notes provide evidence of friendships, nicknames, and “inside jokes” that are never recorded in formal government documents.

The History Room has a comprehensive collection of Clear Lake High School Year Books from 1909 through 2024.  Some volumes are available to check out so you can prepare for the upcoming high school reunion.

We have a long term project to scan all of the Clear Lake High School Year Books.  Click this Link to view the scanned Year Books.

The History Room has a complete collection of the R.L. Polk Directories published annually from 1938 through 2024.  The directories were published for Mason City but included information for surrounding communities, including Clear Lake.  The Mason City Library History Room has Polk Directories issued prior to 1938, but only the 1900 volume contains Clear Lake information.

The Polk Directories (officially R.L. Polk & Co. City Directories) were comprehensive yearly guides that recorded the residents, businesses, and social fabric of American cities long before the widespread use of telephones.

Founded in 1870 by Ralph Lane Polk in Detroit, these directories became the gold standard for urban data, eventually covering over 1,000 cities across North America.

Unlike modern phone books, which only list people with active phone lines, Polk Directories were compiled by canvassers who went door-to-door. This makes them significantly more detailed:

• Individual Listings: Includes the head of household’s name, their occupation, and their employer.
• Family Details: Often lists the spouse’s name in parentheses (e.g., Smith, John (Mary)) and may indicate if a woman was a widow.
• Home Status: Notations like “h” (homeowner), “r” (resident/renter), or “bds” (boarder) show the person’s living situation.
• Numerical Street Guides: A “Criss-Cross” index where you can look up an address to see who lived there, which is invaluable for property history.
• Business & Social Directories: Listings for local churches, schools, secret societies (like the Masons), and “Yellow Page” style business advertisements.

Today, Polk Directories are primary sources for historians, genealogists, and urban researchers.   While the U.S. Census happens every 10 years, Polk Directories were often published annually, allowing researchers to track a family’s movement or a business’s growth year-by-year.  They can identify when businesses or homes were built at an address and how ownership changed over the years.

The Library has a collection of maps from various publications.  The maps that have been digitized are available in our Collections Catalog.

Sanborn Maps-

The History Room has a set of Sanborn Maps for Clear Lake that include the years 1893, 1899, 1909, 1916, 1931 and 1950.  The maps are printed in a 24” by 30” format, folded in half.

Created by the Sanborn Map Company starting in 1867, these were not general-purpose street maps. They were Fire Insurance Maps—highly technical, color-coded diagrams designed to help insurance underwriters estimate the risk of a building burning down without having to visit the site in person.

Sanborn maps are famous for their consistent, detailed shorthand. Because they were meant to assess fire risk, every detail relates to how a building was constructed and what was inside it.

• The Color Code: This is the most important feature for a quick “read” of a neighborhood:
• Yellow: Wood-frame construction (high fire risk).
• Pink/Red: Brick construction.
• Blue: Stone, concrete, or cinder block.
• Gray/Green: Fire-resistant or “fireproof” materials (like adobe or iron).
• Building Details: Small numbers indicate how many stories a building has. An “x” on the roof indicates a shingle roof, while a dot might represent a tin or slate roof.
• Specific Labels: You will see “D” for dwelling, “S” for store, and “A” for “auto house” (garage). Large factories often have specific rooms labeled (e.g., “Boiler Room,” “Paint Shop”) because those areas posed specific fire threats.

Plat Maps and Plat Maps

The History Room and Historical Society have a collection of Plat Maps including the City of Clear Lake and surrounding townships of Cerro Gordo County.

A Plat Map (also known as a “plat”) is a scale drawing of a specific area of land—such as a neighborhood, subdivision, or township—that has been officially surveyed to show how it is divided into individual lots. While city directories tell you who lives there, a plat map defines the legal boundaries of what they actually own.

In the 19th and early 20th centuries, “Plat Books” were published for rural counties. These are a goldmine for historians because they often printed the actual name of the landowner directly on the parcel of land. You can open a 1905 Plat Book and see exactly how many acres your ancestors farmed and who their neighbors were.

A plat map is designed to be a permanent legal reference. It typically includes:

• Lot and Block Numbers: Land is often divided into “Blocks” (large sections) and then further into “Lots” (individual parcels). Your legal address might be “Lot 4, Block B.”
• Dimensions and Bearings: Precise measurements of each property line, often written in “Metes and Bounds” (e.g., “North 40 degrees East, 120 feet”).
• Easements: These are crucial “invisible” lines. They show where utility companies have the right to run power lines or pipes, or where a shared driveway exists.
• Access Points: It marks dedicated public streets, alleys, and “rights-of-way” that ensure every lot has a way to be reached without trespassing.

Clear Lake Newspapers-

Newspapers were published in Clear Lake beginning in 1860 with the Independent, through today’s Mirror-Reporter.  Read about the history of the Clear Lake newspapers at Clear Lake Newspaper History

The History Room has microfilm of all Clear Lake newspapers from 1860 to 2016.  The newspapers from 1860 to 1961 have been digitized through a grant in memory of the Teed Family and can be searched on-line at :Clear Lake.History Archives website

Other Newspaper Resources-

Many of the Mason City newspapers are digitized and searchable on-line using paid services such as Newspapers.com and Newspaper Archive.com.  

The History Room has a collection of  scrap books of newspaper clippings from the late 1870’s through 1948.  Volumns 1 through 6 covering the period 1900 through 1932 was indexed by Bob Ingersoll. The index lists persons, events and/or organizations by page for each volume.

Before the digital age of “bookmarks” and “Pinterest boards,” people used scrapbooks to save the ephemeral information that mattered most to them. These are essentially curated “greatest hits” of a specific person’s life or interests, snipped from the daily paper and preserved in a book.

Click the button below to learn more and view the list of Scrap Books available.