For SRTM 90m DEM, follow this link

http://www.cgiar-csi.org/data/srtm-90m-digital-elevation-database-v4-1

While for ASTER 30m DEM data:

http://gdem.ersdac.jspacesystems.or.jp/

Also, this link has multiple resources from where you can access DEM data:

http://www.terrainmap.com/rm39.html

Hope this helps!

Hi!

Gobal DEM --> GTOPO --> https://lta.cr.usgs.gov/GTOPO30

Gobal DEM with bathymetry --> ETOPO --> https://www.ngdc.noaa.gov/mgg/global/global.html

As Jibran worte, you can use Earth Explorer for download --> http://earthexplorer.usgs.gov/

In future --> ALOS DEM:

http://www.eorc.jaxa.jp/ALOS/en/aw3d30/index.htm

http://www.eorc.jaxa.jp/ALOS/en/aw3d/index_e.htm

TanDEM-X DEM:

https://tandemx-science.dlr.de

Hi there!

The below link is good for downloading Aster GDEM.

http://gdex.cr.usgs.gov/gdex/

Bhuban,ISRO.

GLCF

USGA earth explorer.

Try GEBCO 2014 grid. It's a global grid of ocean depth and land height compiled from different sources in 30 arc seconds. It's up to date and well documented. 

http://www.gebco.net/data_and_products/gridded_bathymetry_data/gebco_30_second_grid/

Using kml file from Google earth : http://www.gelib.com/srtm-kml.htm

http://www.gelib.com/srtm-kml.htm

Hi ,ALL

Thank you very much for all

Special thanks to Dr. Neumann ,Dr.  Claudia , Dr.  Ullmann and Dr. Jibran Khan

Now I use this website.

http://rda.ucar.edu/#!lfd?nb=y&b=topic&v=Land%20Surface

need registration

It contains more information about Digital Elevation Models for Relief (topographic + bathymetric)

Regards

Abdel Rahim

Hi Abdel,

you can download free 90m Digital Elevation Data from this site

http://srtm.csi.cgiar.org/

here is a youtube link to how to do it

https://www.youtube.com/watch?v=4-V54RHNFPU

and also a file to lead you to do it

http://www.cgiar-csi.org/data/srtm-90m-digital-elevation-database-v4-1

i have also attached a file on "DEM hydro-processing with ILWIS Open 3.4"

https://www.youtube.com/watch?v=4-V54RHNFPU

Dear Abdel

One of the best sites for DEMS, especially if you are looking for contours in counties where contour data is restricted is ASTER GDEM gdem.ersdac.jspacesystems.or.jp/‎

ASTER GDEM have other websites e.g. https://asterweb.jpl.nasa.gov/gdem.asp

Regards

Dr John Studley

GEBCO and C-Map for bathymetry

http://www.gebco.net/

http://www.chsmith.com.au/Products/CMAP-Bathymetric-Charts.html

SRTM, ASTER, Cartosat DEM for topography

http://www.ngdc.noaa.gov/mgg/global/global.html

https://www.ngdc.noaa.gov/mgg/global/relief/ETOPO1/data/ice_surface/grid_registered/georeferenced_tiff/

For topography and bathymetry, the Global Multi-Resolution Topography Data Synthesis (http://www.marine-geo.org/portals/gmrt/) is a great resource not yet listed. Data are accessible via web services (http://www.marine-geo.org/tools/web_services.php#gmrt) or web portal (http://www.marine-geo.org/tools/maps_grids.php)

OpenTopography provides access to SRTM GL3 (90m) and the new global GL1 (30m) dataset via web portal (http://opentopo.sdsc.edu/gridsphere/gridsphere?cid=geonlidar&platform=Satellite%20Data&format=sd) and web service (http://www.opentopography.org/index.php/Tools/developers)

I am not sure about Bathymetry, but Earthexplorer is a quick and easy way to get free 1x1 degree tiles of 1-arc second void filled SRTM DSM in Arc BIL ogrid of GeoTiff format.

http://earthexplorer.usgs.gov/

Next 10 offers processed DTMs for purchase (vegetation and buildings removed) with enhanced vertical resolution over the free products.

http://www.intermap.com/data/nextmap-world-10

http://earthexplorer.usgs.gov/

http://www.intermap.com/data/nextmap-world-10