USGS Digital Elevation Model, Spatial Data Transfer Standard Format (DEM/SDTS)

Description: Elevation data derived directly from USGS native format DEMs. Spatial content is equivalent to DEM, but physical format and metadata content are more robust. 7.5-minute data (1:24,000 & 1:25,000 scale) and 1:250,000 scale are available in SDTS format. Native format data continue to be produced and sold.

Available for free? Yes.

Web Pages and FTP Sites:

USGS Geographic Data FTP Site

USGS Geographic Data Download Site

Ask USGS

SDTS Home Page

USGS Digital Elevation Model, GeoTIFF Format

Description: Elevation data derived directly from USGS native format DEMs. This is an experimental format and is not available for sale. GeoTIFF DEMs are implemented as 16-bit TIFF images to preserve absolute elevation values. 16-bit data, while allowed by the TIFF 6.0 standard, is not widely implemented in TIFF viewers, so these files may or may not be viewable in other software.

Available for free? No. DEM data in GeoTIFF format is not a USGS product.

Web Pages and FTP Sites:

Sample Data FTP

USGS Digital Orthophoto Quads (DOQ), Native USGS Format

Description: DOQs are aerial photographs that have been rectified to have the scale and geometry of a map, and joined or cut to cover the same area as USGS topographic map quadrangles. These images typically have a ground resolution of 1 meter. They are packaged in quarter-quad format (four physical files to one 1:24,000 scale quadrangle) because of the very large file sizes. Most DOQs are 8-bit grayscale images, but 24-bit color images are also available in some areas. The native format of these files is a ban-interleaved-by-line (BIL) image with a keyword text header at the beginning of the file.

Available for free? No.

Web Pages and FTP Sites:

General information about DOQs

Ask USGS

Sample Data FTP

USGS Digital Orthophoto Quads (DOQ), GeoTIFF Format

Description: DOQs are aerial photographs that have been rectified to have the scale and geometry of a map, and joined or cut to cover the same area as USGS topographic map quadrangles. These images typically have a ground resolution of 1 meter. They are packaged in quarter-quad format (four physical files to one 1:24,000 scale quadrangle) because of the very large file sizes. The GeoTIFF version of this product is exactly the same image as the native format.

Available for free? No.

Web Pages and FTP Sites:

DOQ in GeoTIFF

General information about DOQs

Ask USGS

Sample Data

USGS Digital Orthophoto Quads (DOQ), JPG w/ Native Header Format

Description: DOQs are aerial photographs that have been rectified to have the scale and geometry of a map, and joined or cut to cover the same area as USGS topographic map quadrangles. These images typically have a ground resolution of 1 meter. They are packaged in quarter-quad format (four physical files to one 1:24,000 scale quadrangle) because of the very large file sizes. Most DOQs are 8-bit grayscale images, but 24-bit color images are also available in some areas. The native format of these files is a JPEG encoded image with an accompanying header file to provide metadata.

Available for free? No.

Web Pages and FTP Sites:

General information about DOQs

Ask USGS

USGS Geographic Names Information System (GNIS)

Description: The Geographic Names Information System (GNIS) contains name and locative information about almost 2 million physical and cultural features located throughout the United States and its Territories. GNIS was developed by the USGS in cooperation with the U.S. Board on Geographic Names (BGN) to promote the standardization of feature names.

Available for free? Yes.

Web Pages and FTP Sites:

GNIS FTP Site

USGS Land Use and Land Cover Data (LULC)

Description: The Land Use and Land Cover (LULC) data files describe the vegetation, water, natural surface, and cultural features on the land surface. The USGS provides these data sets and associated maps as a part of its National Mapping Program. The LULC mapping program is designed so that standard topographic maps of a scale of 1:250,000 can be used for compilation and organization of the land use and land cover data. In some cases, such as Hawaii, 1:100,000 scale maps are also used. Global Mapper currently supports the GIRAS format of these files. The grid cell (CTG) format is not yet supported.

Available for free? Yes.

Web Pages and FTP Sites:

USGS Geographic Data Download Page

NOAA DSDATA Geodetic Control, SDTS Format

Description: Control point data from the National Oceanic and Atmospheric Administration (NOAA), National Geodetic Survey (NGS). Recently made available in SDTS format. Note that Global Mapper will display only the SDTS version of these data, and will not display the native NGS data sheet format.

Available for free? Yes.

Web Pages and FTP Sites:

NOAA DSDATA Home Page

Sample Data FTP

NOAA TerrainBase Elevation Data

Description: A collection of public domain Digital terrain models (DTM) from the NOAA National Geophysical Data Center. This collection includes an improved 5-minute DTM of land and ocean values for the entire world.

Available for free? Yes. Also sold on CD.

Web Pages and FTP Sites:

NOAA TerrainBase Home Page

Sample Data FTP

Canadian Digital Elevation Data (CDED)

Description: The CDED consists of an ordered array of ground elevations at regularly spaced intervals. It is based on National Topographic System (NTS) maps at the 1:250,000 scale. Nearly complete coverage of Canada is available. CDED data use the same physical format as USGS DEM data, and therefore can be displayed by Global Mapper.

Available for free? No. Price information is available at the CDED web site below.

Web Pages and FTP Sites:

Center for Topographic Information

Standards and Specifications

PNG Image with World File

Description: With the appropriate World File (typically with a PNGW extension), a PNG image may be positioned geographically in Global Mapper.

Available for free? Sometimes.

Web Pages and FTP Sites:

AutoCAD DXF (Drawing Interchange File)

Description: The DXF format is a tagged data representation of all the information contained in an AutoCAD drawing file. Tagged data means that each data element in the file is preceded by an integer number that is called a group code. A group code's value indicates what type of data element follows. This value also indicates the meaning of a data element for a given object (or record) type. Virtually all user-specified information in a drawing file can be represented in DXF format.

Available for free? Sometimes.

Web Pages and FTP Sites:

Autodesk AutoCAD DXF Documentation

ESRI Shapefiles

Description: A shapefile stores nontopological geometry and attribute information for the spatial features in a data set. The geometry for a feature is stored as a shape comprising a set of vector coordinates. Global Mapper supports loading Shapefiles directly from .tar.gz files, so you do not need to uncompress your Shapefile data if you do not want to.

Available for free? Yes.

Web Pages and FTP Sites:

The National Atlas of the United States of America

Surfer Grid (ASCII and Binary) Format Files

Description: Surfer Grid Format files are used to store a grid of elevation data. This format is supported by several software packages, with Golden Software's Surfer package being the most prominent. Global Mapper support both the import and export of this format.

Available for free? Sometimes.

Web Pages and FTP Sites:

Golden Software: Surfer Product Information

Canada 3D Files

Description: Canada3D is a DEM produced by the Canadian Forestry Service, Ontario region. The DEM consists of an ordered array of ground elevations providing coverage of the entire Canadian landmass. It has been derived from the cells of the CDED at the 1:250 000 scale. Canada3D is available in two forms: grids regularly spaced at 30 or 300 arc-seconds. Canada3D 30 and 300 are recorded separately in ASCII text file format. The elevation values are expressed in meters with respect to mean sea level (MSL), in accordance with the North American Datum of 1983 (NAD83).

Available for free? Yes

Web Pages and FTP Sites:

Center for Topographic Information

Global 2' Elevation Data (ETOPO2)

Description: A newly constructed global elevation data base gridded at 2-minute (latitude-longitude) resolution The ETOPO2 data set contains both land data from the Global Land One-kilometer Base Elevation (GLOBE) project as well as seafloor topography from various sources.

Available for free? No

Web Pages and FTP Sites:

ETOPO2 Home Page

GLOBE (Global Land 1-km Base Elevation) Data

Description: The Global Land One-kilometer Base Elevation (GLOBE) digital elevation model is the most thoroughly designed, reviewed, and documented global digital elevation dataset to date. GLOBE comprises a global 30 arc-second latitude-longitude array, with land areas populated with integer elevation data. GLOBE is available on the World Wide Web, and on CD-ROM in a format convenient for image processing and raster geographic information systems (GIS). Full GLOBE documentation is available on the CD-ROM and Website. To load GLOBE data into Global Mapper, first download and uncompress the data files (if necessary). Name the large elevation data file with the .bin extension. Then download the GeoVu header for the tile that you just downloaded and place it in the same directory as the .bin file. Finally, use the File->Open menu item to load the .bin file.

Available for free? Yes

Web Pages and FTP Sites:

The Global Land 1-km Base Elevation (GLOBE) Project

GLOBE FTP Site

Arc/Info Binary Grid

Description: The Arc/Info Binary Grid format is the format used by Arc/Info internally to store elevation grids.

Available for free? Sometimes.

Web Pages and FTP Sites:

LizardTech MrSID Data

Description: The LizardTech MrSID format is a raster format which uses wavelet-based compression techniques to achieve extremely high compression ratios for raster data sets.

Available for free? Sometimes.

Web Pages and FTP Sites:

LizardTech Home Page

Arc/Info Export Format (E00)

Description: The E00 format is the Arc/Info exchange format for groups of vector coverage's.

Available for free? Sometimes.

Web Pages and FTP Sites:

ERMapper Compressed Wavelet (ECW) Format

Description: The ECW format uses a wavelet based compression method to achieve extremely high compression ratios on airphotos and scanned topographic maps. Typical compression ratios range between 20:1 and 100:1 which maintaining a very high level of quality. In addition, ECW format data can be dynamically served over the internet using ER Mapper's Image Web Server. Global Mapper can load ECW format data both from local files and directly from Image Web Server. Several sample web served links are built into Global Mapper for the convenience of the end user.

Available for free? Sometimes

Web Pages and FTP Sites:

ER Mapper Home Page

Image Web Server Home Page

DTED (Digital Terrain Elevation Data) Format

Description: In support of military applications, the National Imagery and Mapping Agency (NIMA) has developed standard digital datasets (Digital Terrain Elevation Data (DTED)) which is a uniform matrix of terrain elevation values which provides basic quantitative data for systems and applications that require terrain elevation, slope, and/or surface roughness information.

Available for free? Yes

Web Pages and FTP Sites:

GIS Data Depot Download Center

MapInfo MIF/MID and TAB/MAP Formats

Description: The MapInfo MIF/MID and TAB/MAP formats are both formats used by the MapInfo software package to store vector map information.

Available for free? Sometimes

Web Pages and FTP Sites:

GIS Data Depot Download Center

NIMA GNS (GeoNet Names Server) Format

Description: NIMA is now able to provide complete files of geographic names information covering countries or geopolitical areas. The files are not in customary gazetteer format, but are in a special format amenable to input into geographic information systems, databases, and spreadsheets, giving end users powerful capabilities for data analysis, manipulation, and display. The files contain names for all types of features. The file fields are described in description of file fields. Names are in reading order. The files are ASCII files and are tab delimited. The files are zip files. Dates indicate when the file was generated from the database.

Available for free? Yes

Web Pages and FTP Sites:

NIMA GNS Data Site

MicroStation DGN Format

Description: MicroStation DGN format files are files compatible with Bentley's MicroStation product line. Global Mapper can import DGN files created with MicroStation prior to MicroStation v8.

Available for free? Yes

Web Pages and FTP Sites:

Bentley System, Inc. Home Page

SRTM (Shuttle Radar Topography Mission)

Description: The Shuttle Radar Topography Mission (SRTM) data products result from a collaborative mission by the National Aeronautics and Space Administration (NASA), the National Imagery and Mapping Agency (NIMA), the German space agency (DLR) and Italian space agency (ASI), to generate a near-global digital elevation model (DEM) of the Earth using radar interferometry. The SRTM-1 (1 arc-second) and SRTM-3 (3 arc-second) digital elevation models are being developed from the SRTM C-band radar observations for selected regions to satisfy the needs of NASA related projects and to speed the evaluation of acquisition and processing and applications algorithms.

Available for free? Yes, SRTM data is available in GeoTIFF, Arc Grid, and HGT formats, all of which Global Mapper supports.

Web Pages and FTP Sites:

SRTM Home Page

USGS Seamless Data Distribution Center (Arc Grid and GeoTIFF Formats)

SRTM FTP Site (HGT Format)

Geosoft Binary Grid Files

Description: The Geosoft Grid format is a binary grid format for storing elevation data. This format is used by software like Geosoft's Oasis Montaj product. Global Mapper v6.05 and higher can directly import and export this format.

Available for free? Varies.

Web Pages and FTP Sites:

GeoSoft

Hypack Matrix Files

Description: The Hypack Matrix format is a grid format typically used for storing bathymetric data used in marine surveying. This format is used by software from Hypack, Inc. Global Mapper v6.07 and higher can directly import this format.

Available for free? Varies.

Web Pages and FTP Sites:

Hypack, Inc.

DHM - Swiss DEM Files

Description: The DHM format is a digital height model used by the Swiss government. Global Mapper v6.08 and higher can directly import this format.

Available for free? Samples are available for free.

Web Pages and FTP Sites:

Swiss Topo DHM25 Page

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Lowrance USR

Description: The Lowrance USR file format is used to store user waypoints and track logs from GPS devices. These files can be loaded into Global Mapper v6.09 and above.

Available for free? Yes.

Web Pages and FTP Sites:

Lowrance Electronics