Internet Mapping Services

An Internet Mapping Service allows government and other agencies to provide access to maps and other data  through a web site. This information can be viewed online, added to a map as a service, or often downloaded as data layers for other maps.

International

The Lincoln Institute of Land Policy has produced the Atlas of Urban Expansion which provides information about the geographic and quantitative dimensions of urban expansion and its key attributes in cities the world over.

The Armed Conflict Location and Event Data Project is the most comprehensive public collection of political violence and protest data for Africa, South Asia, Southeast Asia, the Middle East, Central Asia and the Caucasus, Latin America and the Caribbean, and Southeastern and Eastern Europe and the Balkans.

Federal Government Mapping Services

Investigate census data easily via Census.Data.Gov, (scroll down the page to see maps, tables, visualizations, microdata and more).  The American Community Survey includes the handy QuickFacts tool and a Data page with links to many more tools and apps.

The Bureau of Labor Statistics offers many data sets and tools related to economics and jobs on a regional and national level, including a couple of customizable visualizations.

The Centers for Disease Control has a Data and Statistics page which has survey data regarding various conditions and a number of data visualization and access tools.

Everything you could want to know about education is collected by and available at the National Center for Education Statistics, including a set of online data tools.  A somewhat different list of datasets is available from the Department of Education , including the College Scorecard for all institutions of higher ed in the US.

The Bureau of Justice Statistics includes statistics about crime, criminal offenders, victims of crime, and the operation of justice systems.  Their data sources are listed here.

The Department of Homeland Security produces the annual Yearbook of Immigration Statistics and data tables on related topics.

Lots of interesting statistics from the IRS at the Tax Statistics page.  

The USDA has a data page listing twenty different research services, including the Economic Research Service and the National Agricultural Statistics Service.

The Bureau of Transportation Statistics tells you all about various modes of transportation, including a Geospatial Portal with mapping apps and an Information Gallery.

The EPA provides Envirofacts and EnviroMapper in order to learn about your area.  Scroll down to the bottom of the site to find the Data page.

The USGS manages the National Map — “the nation's topographic map for the 21st century.”

State and Metropolitan Mapping Services

Almost every state and large metropolitan area has an internet mapping service to provide public access to geospatial data collected at the taxpayers’ expense. Your best approach is to search (for example, using Google or other search engine of your choice) for the phrase “GIS” and whatever state or locality you are interested in.

For example, a search for “GIS and Chicago” will result in (among others) the City of Chicago GIS page. If you perform the same search with the search terms “GIS and Boston,” you can use either Boston Open Data or Massachusetts GIS, a state agency.   Some state departments might have their own services, such as the NYS DEC Mapping Gateway.  Some web sites develop as part of specific policy initiatives, such as Data-Driven Detroit, the Syracuse Community Geography project,  or The Greater New Orleans Community Data Center. As a final example, here is an entire page of IMS sites found by looking for information on New York City and GIS.

One may also find a wealth of information by looking for mapping resources related to a particular event or theme. For example, here is a page of resources on Hurricane Katrina and Other Natural Disasters (including a new section on COVID-19 resources).