Quick Links: County Maps of all 50 U.S. States

If you ever need a map showing the counties of just one state, complete with county name labels, you can find links to those on the aptly titled County Maps of all 50 U.S. States page.

For example, clicking the Iowa County Map link on that page will take you to the County Lines on Google Maps tool already filtered to show just Iowa counties, complete with labels.  It looks like this:

Once on the page, you can zoom in, turn on city limits and townships in the lower left corner, and so on.

Also, if you need to find the county you are currently in (based on your mobile device's location), try the What County Am I In? tool.  And companion tools What City Am I In? and What Township Am I In? -- they do what they say on the tin. ;)

Hope these quick links make it easier to get to the state county map that you need!

Sharing Maps just got a lot more powerful

Now, when you share a link to any live map tool on, the recipient will be taken to exactly the same view you were seeing when you shared it.  The link you share will remember:

So, how do you share the link to the live map?

Easy.  You can either:
  • Use the "Share Map" button on the left side of the map, then right click the link that appears and choose "Copy link address".  (Then paste it in an email, website, etc.) It looks like this: 
Share Map button on map tools (click to be taken to the live map)

  • OR, simply copy/paste the URL shown in your browser window's address bar.  It looks like this: 

Now, using the above example, when the recipient of your shared link clicks the link, they'll be taken to the County Lines on Google Maps tool, zoomed in on south-central Florida, see city limits, and have a blue marker visible just above Sanibel.

This helps ensure the recipient of your shared link sees the same map you were viewing.  But not just that -- rather than being a static image, it will be a live map that they can further explore.

(Note, ad blockers may interfere with this functionality, so if you have any issues with sharing, you might try disabling ad blockers and refresh the page.)

Happy sharing! RSS feed changing

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Create a custom Color-Coded map from a spreadsheet containing Counties or ZIP Codes

The Custom Areas on Google Maps tool is being used by hundreds of people per day to create and view custom delivery area maps, service area maps and sales territory maps -- helping many small businesses during challenging times.

But dozens of people have asked if they could color-code multiple areas on the same map.  For example, people wanted to create a color-coded map to show delivery zones, real estate demand, all of their company's sales territories, tax incentive zones, incident case rates, climate/environmental classifications and more. 

Now you can!

Just go to the new Custom Color-Coded Maps tool and use the easy-to-use form below the map.  Using the form, you can map by:
  • County Names + State Abbreviations (2 columns) or
  • 5-digit ZIP Codes (1 column) or
  • 3-digit ZIP Codes (1 column) -- best for very large regional or national coverage
All you'll need to make the map is a spreadsheet saved in Google Sheets containing the geography you wish to map (e.g. counties, ZIP Codes), the data you want to show (e.g. zone name, salesperson) and the colors you want the map to use.  The map is live-linked to the spreadsheet, so if you change the spreadsheet, those changes will automatically be reflected the next time you view the map web page.

Just go to the form and it will step you through exactly how to do everything.  You can have your custom map up and running in as little as a few minutes.

Sample Maps

Click each map to go to the interactive Google Map and explore.

Map of sales territories based on counties:

Custom Color Coded Map using Counties

Map of delivery zones based on 5-digit ZIP Codes:

Custom Color Coded Map using 5-digit ZIP Codes

Map of health or environmental territories based on 3-digit ZIP Codes:

Custom Color Coded Map using 3-digit ZIP Codes

Be sure to read the entire form so you know how to format the spreadsheet correctly and make it available to be viewed by the map tool.

Please feel free to share this tool with others who might find it useful, and leave any comments below.  As with any first version, the tool will be made more powerful with time.  

Happy mapping!

Note:  The Custom Color-Coded Maps tool is available for U.S. locations only.  Other countries may be added in the future.

Auto-checking of all Location Facts in Ancestry Family Trees now available

While searching on and FamilySearch, the FREE Historical U.S. Counties Auto-Checker extension for Chrome automatically checks that the county existed in the year you are searching, checks for valid places, warns of boundary changes, and links to historical county lines on Google Maps for the place and years you are searching.

Now, in addition, if you are a Research Hub contributor, the Auto-Checker will ALSO automatically check all U.S. location facts on person profile pages on all family trees! And your MAP links will open into ad-free fullscreen map windows any time you click a MAP link! 

Auto-Check location facts on all family trees

The screenshot above highlights how the tree fact-checking works on any person profile page on any family tree.  A few key features:

  • Quick links to interactive historical county maps for the year of each fact
  • Warnings if the county listed in your fact did not exist for the year of the fact (plus quick links so you can see what counties did exist in that year)
  • For ambiguous place names, possible matches are listed including map links (e.g. if the same township name exists in multiple places in the state, and you didn't list the county)
  • Once you link to the map page, as a contributor, you'll be working with ad-free full-screen maps that you can further explore the dates and places around your area, including both historical and present-day county lines, township boundaries and more.  Details of exactly when each county formed, what counties it formed out of, statutes and more are listed above the map.

Remember, U.S. county boundaries have changed over 17,600 times since America was settled in colonial times. Don’t sabotage your search for ancestors by not knowing the correct county for the historical years you are researching.  Install for free today and never let an ancestor fall of the map again!


FREE version:  While using any Search form on or, the Auto-Checker automatically checks that the county existed in the year you are searching, checks for valid places, warns of boundary changes, and links to historical county lines on Google Maps for the place and years you are searching!

CONTRIBUTOR version:  Everything the free version does PLUS checks all of the U.S. location facts on person profile pages on all family trees.  The check includes everything listed in the bullet points above.  Plus you get access to ad-free fullscreen versions of all map and search tools on  NEW:  You can pause tree fact-checking at any time with the "Pause Auto-Checker" button in the Chrome extension popup.  Note: tree fact-checking is not available for FamilySearch family trees.

The Historical U.S. Counties Auto-Checker Chrome extension makes use of the award-winning Research Hub’s Historical U.S. Counties on Google Maps tool, underpinned with the complete dataset of the authoritative Newberry Atlas of Historical County Boundaries.

Where It's At: Walking the perimeter of this city = Walking from Philadelphia to Denver

If you were to walk the perimeter of this U.S. city's city limits, you would cover 1,562 miles (2,513 km), which is roughly the same distance as walking from Philadelphia to Denver.*

Here's what that distance looks like:

Philadelphia to Denver

And the answer is:

Houston city limits

Well, of course, Houston.  Isn't everything big in Texas?  The city covers an area of 672 square miles (1,739 sq km), and all those little (big) tendrils shown by the dark blue lines above make its perimeter add up to this whopping 1,562 miles!  Want to zoom in and see the details?  Explore the city limits of Houston here.

So, Houston takes the prize for the longest perimeter of any city in the United States.  If you're curious, #2 is Buckeye, AZ at 646 miles (1,039 km), and #3 is Charleston, SC at 619 miles (997 km).

Bonus trivia:  If Houston has the longest perimeter, does it also have the largest area?  

No.   That distinction goes to Jacksonville, FL at 875 square miles (2,265 sq km).  (If you include boroughs in this calculation, the winner is Sitka, AK at 2,870 sq mi of land area (7,433 sq km))

Want to explore your city?  Check out the What City Am I In? tool on this website.

* this is the "as the crow flies" distance from Philadelphia to Denver.  If you were to actually walk from Philadelphia towards Denver along legal routes, according to Google Maps, you'd make it to about the eastern border of Colorado.


NEW: Share your map with one click

Now available on most map tools on, use the "Share Map..." button to create a shareable link that remembers all of the following:
  • which map tool you are using (e.g. City Limits on Google Maps, Elevation on Google Maps)
  • what point you had clicked on the map (or had searched for using the "Search places" box above the map)
  • how far zoomed in or out you want the map to display
  • optionally, a title for your map
Here's an example, sharing a map from the City Limits on Google Maps tool, centered on Ocala, Florida:

Share Map button on City Limits on Google Maps tool

In this example, I have added a map title where it says "title=" at the end of the text box.  This produces the following link (click to see the finished result):

Or, to make it more pretty, you can title the link and embed the link address, like this (again, click to see the finished result):

And here's another example, showing an elevation contours map centered on the Gangtey Monestery in Bhutan:

Share Map button on Elevation on Google Maps tool

Links for this map:

To use the Share Map button:
  1. open the map tool of your choice in the Map Tools menu in the upper left
  2. center the map where you want it either by clicking the map or using the "Search places" box above the map
  3. zoom in or out on the map using the + and - buttons on the map
  4. click the "Share Map..." button on the left side of the map
  5. right-click the link that appears and click "Copy Link Address" (or, if you want to add a custom title, edit the map title after "title=" in the textbox that appears and then copy the text in the textbox)
  6. paste the link whereever you want to share it (e.g. another website, an email, a blog post, a forum, facebook, twitter etc)

Power tip:  To share maps containing more than just a point, check out the map tools in the Custom Map Tools menu in the upper left corner of the website.  For example, create custom delivery area maps using the Custom Areas using ZIP Codes tool

Hope you find this new functionality useful!

Happy map sharing!