This map combines the familiar interface of Google maps with the story-telling power of data from GIS (Geographical Information System) servers. Please pan around the map and find a grossly shaped congressional district - there are many! Make your own custom map link that automatically highlights one of those districts when the map opens. Show that map to your congress representative and ask if they are in favor of gerrymandered voting districts. When they say "no" then ask them to co-sponsor The Fair Representation Act (Introduced 06/26/2017). H. R. 3057 will go a long way toward eliminating gerrymandering and fixing the partisan extremism in congress by implementing ranked choice voting based on larger districts and with several people elected to the House of Representatives from each district. For more information please see this announcement on

Read Me

Due to a limit placed by Google, this map might stop working until tomorrow. See more below.

Everyone is welcome to share and repost any of these map links. There is no need to ask first. Please follow these simple rules:

1. When you post a map link, also post a link to this "Map Tips" page. Here is the link to post.

2. It is preferred that you use a map link instead of embedding a 'live' map. This relates to the limit imposed by Google - see more below.

3. Include in your post a credit thanking

4. Do not use these map links for any commercial purpose.

Be patient. The data that the map displays comes from several federal servers. Sometimes it may take a few seconds for data to appear on the map. It all depends on how much other work the servers are trying to do at the same time.

The map is displayed by Gmap4 which is an enhanced Google map viewer. Beginning with version 3 of this map, the ability to turn on an overlay that shows the congressional district boundaries is now a permanent built-in feature of Gmap4. Additional related features have been added.
The congressional district boundaries are current as of January 2017 and correctly show the districts for the 115th congress.

U.S. House Bill 1102 would require all states to appoint an independent commission for the purpose of drawing congressional boundaries. This would go a very long way towards ending the goofy gerrymandered boundaries you can see as you surf the map. For a link to the text of this bill, scroll down on this page. To see the list of co-sponsors and track this bill go to

The states that already use an independent commission to draw congressional district boundaries are Alaska, Arizona, California, Idaho, Montana and Washington.

Action Item: Use this map to show your representative examples of grossly shaped congressional districts. If your representative is not already a co-sponsor of H.R. 1102, then ask them to either (1) become a co-sponsor or (2) explain to you exactly why they are in favor of gerrymandered congressional districts.

Please be aware that the map might stop working until the next day.

Each time the map is opened, there is some code that is downloaded from Google's servers. This code is the Application Program Interface (API) and it is the magic that makes Google maps work. Google allows each domain (i.e. to download the maps API 25,000 times per day (Pacific time) for free. When that limit is reached, then all maps from my domain stop working until the next day. A new day starts at midnight Pacific time.

Dear Google,

Sometimes you have to stand up and fight for your beliefs whether you are an individual or a huge corporation. And Google did so early in 2017 when it signed the letter, along with other tech firms, opposing Trump’s first executive order on immigration. If you agree with me that gerrymandered voting districts are a Bad Thing, then you now have an opportunity to help me help you do something about that.

Please consider allowing my domain to download the Google map API more then 25,000 times per day. It is going to be tough for any politician to deny that a voting district is likely gerrymandered when it’s bizarre shape is highlighted and staring them straight in the face from an online screen.

Yes, I know Google has a program whereby a 501c3 can apply to be allowed to exceed the 25,000 daily download limit for the maps API. However, since the anti-gerrymander message I am conveying is political, this work does not qualify to be a 501c3.

About Gerrymander

Want to know who decides where voting district boundaries are drawn in your state? The Brennan Center for Justice (New York University School of Law) has complied that information here. This analysis covers both congressional districts and state legislature districts.

The Brennan Center also posts periodic updates on the status of the various lawsuits underway in several states challenging gerrymandered voting districts. Here is their late April 2017 update.

Another excellent source of information on the status of lawsuits that challenge gerrymandered voting districts is this Election Law Blog.

How to use this map

Open the Google + GIS Congressional District Map

Long link:

Short link:

Basic Map Tips

The map will only open if your browser is online.

If you open the map on a desktop or laptop computer then you will see a mouse-oriented interface. If you open the map on a mobile device then you will automatically see a touch interface.

To search on an address, coordinates or a placename, click Menu ==> Search. A search bar will appear at the top of the screen. After the map re-centers at the thing you searched for, then click the map and the popup will show data for that congressional district.

To get a custom map link that will replicate the map you see on your screen, click Menu ==> Link to this map. Email the link to yourself and open it on your cell phone. Then decide if you want to change the zoom level (z parameter) in the link so your map looks good when someone opens it with a cell phone. Here is the documentation on the link parameters that Gmap4 understands.

To turn on geolocation, click Menu ==> My location.

To change the basemap, click the basemap button (next to the Menu button).

The map has several built-in overlay layers that can be turned on/off. One of those built-in layers will show the congressional district boundaries. To see the list of overlays click the basemap button and then look under the "Overlay" heading. Mobile users will need to scroll down.

An overlay layer with a number in front of it is 'on'. Click a layer name to turn it on/off. The highest numbered layer is "on top". Usually the "top" layer can be clicked and a popup will appear showing information about the thing that you clicked.

Bizarre District Examples

Each map link below will show the congressional districts for one state and have one of those districts highlighted. The example from Michigan has a particularly bizarre shape. The fact that there are examples from 21 states shows that gerrymandering is a widespread problem.

While some of these highlighted district seats are held by democrats, most of these seats are held by republicans.

Alabama 2nd,2

Arizona 3rd,3

Colorado 1st,-104.889008&z=10&t=h&congress=CO,1

Connecticut 1st,1

Georgia 11th,-84.642578&z=9&t=h&congress=GA,11

Illinois 11th,-88.143096&z=10&t=h&congress=IL,11

Kentucky 1st,1

Louisiana 6th,-91.007781&z=8&t=h&congress=LA,6

Maryland 7th,-76.857392&z=9&t=h&congress=MD,7

Massachusetts 8th,-70.972840&z=9&t=h&congress=MA,8

Michigan 11th,-83.381897&z=9&t=h&congress=MI,11

Missouri 5th,5

New Jersey 12th,12

Ohio 7th,-82.115723&z=8&t=h&congress=OH,7

Pennsylvania 17th,-75.463501&z=8&t=h&congress=PA,17

South Carolina 2nd,2

Tennessee 3rd,-84.546448&z=7&t=h&congress=TN,3

Texas 2nd,-95.350128&z=10&t=h&congress=TX,2

Virginia 10th,-77.737671&z=8&t=h&congress=VA,10

West Virginia 2nd,2

Wisconsin 3rd,-90.619140&z=7&t=h&congress=WI,3

Create Custom Map Link

There are six different basic ways that anyone can make a map link that will display the congressional district boundary data in a certain way when the map opens.

Display the lower 48 states and all the district boundaries:

Display all the district boundaries centered on a state:,MN

Display all the district boundaries centered on a state and highlight one district:,WI,5

Display the district boundaries for a single state:

Display the district boundaries for a single state and highlight one district:,2

Display the district boundaries for a single district:,IN,2

About the map

About the Data

The data you see on the map comes from federal GIS (Geographical Information System) servers. Each time you open the map, data flows from one or more of those servers to your screen. Those servers are operated by the USGS (The National Map), NOAA/BOEM (Marine Cadastre project) and the EPA.

This map has several main features.

1. District boundaries are extremely easy to see.

As you zoom in, the data layer showing solid colors for the congressional districts disappears. You can then very easily see the boundaries for the congressional districts as bright yellow lines. That yellow line data comes from federal GIS servers that host the "National Map".

After the next census in 2020, the congressional district boundaries will be reviewed and many will be redrawn. The term "gerrymander" refers to drawing district boundaries in order to favor a certain political outcome. For more information on gerrymandering and how elections to the U.S. House of Representatives might have a different outcome without this unlawful practice, just do a google search on: congressional district map gerrymander.

Here is a website with a good explanation of how redistricting works in each state.
Scroll down just a bit and look at the map showing how redistricting works in each state. Regrettably, there are only a few states where an independent commission draws the congressional district boundaries.

2. You can get information about each representative.

If you click (or tap) on a district then you will see a display with all the attribute data the GIS server has for the thing that you clicked. That attribute data will include the representative's name, party affiliation and link to their web site.

3. Door knocking close to a district boundary.

The map data lets you zoom in on the Google aerial and see house-by-house where a district line runs as well as your geolocation. Open this map on your cell phone. Make sure the location services are turned on in your phone. Tap Menu ==> My location. The map will center at your position and the location symbol will follow you as you move.

About Gmap4

The congressional district map is displayed by Gmap4 which is a general purpose enhanced Google map viewer developed by Joseph Elfelt. Gmap4 can be used for any non-commercial purpose.

For more information you can visit the Gmap4 homepage which has a FAQ, list of features, lots of example map links, quick start info (on the Help page) and more.

News about Gmap4 first appears on the Gmap4 Facebook page.

Qustions can be emailed via the Gmap4 contact page.

Log of Map Changes

2017-3-4 Version 4.
Added the button "Bizzare Districts". There are map links with examples from 21 states.

2017-2-24 Version 3.
The congressional district boundaries are now a permanent 'built-in' overlay.
The '&congress=' link parameter has been added. See the section 'Create Custom Map Link' above for details.

2017-1-31 Version 2.
Changed the name of the link in the upper left corner of the map from "About this map" to "Map Tips".
Added the button "Create Map For One District" to the Tips page.
Rearranged the buttons on the Tips page

2017-1-29 Version 1.