Digital Maps Database

DIGITAL MAP FILES COLLECTION

A collection of digital map files of New York City and related geographic areas.

The maps show significant features of the city and region relating to the environment, politics, education, public safety, public health, transportation, business, zoning, and the arts. These files can be used to visualize data from the US Census Bureau and government agencies. Most files are in the format known as KML (Keyhole Markup Language) and are intended for use with Google Earth, Google Maps or Google Fusion Tables. A list of links to additional map resources is provided.

The collection consists of the following elements:

  •  Map files, in KML or ZIP format
  •  A Dropbox folder containing the map files
  •  A Google spreadsheet listing the available map files and additional information

 

 

Format of the Google Spreadsheet

The Google spreadsheet contains the following worksheets:

  1.  Sheet 1 — the list of map files.
  2.  Resources — a list of links to websites with additional map resources.
  3.  Notes on Problem Files (not public) — a list of map files that could not be converted to KML, and a brief description of the problems with the file. This information can be used to set priorities for expanding the collection in the future.
  4.  Column Definitions — description of the format, definition and origin of the data used in each column of Sheet 1.
  5.  Category Notes — explanation of the subject categories used in the “Category” field in Sheet 1.
Important Notes on the Collection
  •  The NYC Department of Information Technology and Telecommunications (DOITT) created many of the collection’s map files on behalf of other agencies. In many cases, questions about a map should be directed to the agency that provided the data, not DOITT.
  •  Some map files in the Dropbox folder are in ZIP form. These are very large files — too large to open in Google Fusion Tables, which has a 100 MB limit. The ZIP files are in the format used by the ESRI company, creator of the popular commercial GIS software product ArcView. ESRI files can be used in open-source map software, such as QGIS. They must be converted to KML for use in Google Earth or Fusion Tables.
Notes on Student Use

Students should be encouraged to:

  1.  Browse the “Category” and “Map Name” columns for interesting maps, to generate story ideas
  2.  Download and explore a map in both Google Fusion Tables and Google Earth
  3.  Explore the web pages listed in the “Resources” sheet, to find explanations of unfamiliar terms or sources for additional maps or data
  4.  Carefully note the originating agency’s name — it may have produced the map, while a different agency may have compiled the data
  5.  Review the date of the map file — it may be out of date
  6.  Visit the web page where the map was found, to see if additional information or an update is available
  7.  Contact the agency that created the map (or the agency that provided the data), to verify the map’s currency and accuracy, and to request an explanation of unfamiliar data labels
  8.  Visit locations on the map in person, to confirm the map is accurate and gather additional information about a location
How to Use the Map Files

NOTE: A user must have a Google account (via Gmail or Google Docs) to use Google Fusion Tables. Using Google Earth requires downloading the Google Earth software to a local computer.

In Google Fusion Tables:

  1.  Download the desired map file from Dropbox to your own computer
  2.  Open Google Docs
  3.  Click on the “Create” label and choose “Table (beta)”
  4.  Click “Choose File” and select the map file on your own computer

Google will open the map file as a new Google Table, and will save the newly created file in your Google Docs account. You will be able to rename the file (if desired) and “Visualize” (view) the data as a table or map.

In Google Earth:

  1.  Download the desired map file from Dropbox to your own computer
  2.  Open Google Earth
  3.  Click on the “File” menu, and choose “Open…”
  4.  Select the map file on your own computer and click “Open”

Google Earth will open the map file as a new layer in your “Temporary Places” folder.

Additional Resources