You may check the following websites:

https://viewer.nationalmap.gov/basic/#/

https://land.copernicus.eu/imagery-in-situ/eu-dem/eu-dem-v1.1

https://search.asf.alaska.edu/#/

Also, this question:

https://www.researchgate.net/post/Where_can_I_download_free_DEMs_higher_than_30m_resolution_in_SE_ASIA_covering_the_Philippines

Dear Litesh Bopche,

Where is your study area? Freely available DEMs with high resolutions are note available for many regions.

You may check the following websites:

https://viewer.nationalmap.gov/basic/#/

https://land.copernicus.eu/imagery-in-situ/eu-dem/eu-dem-v1.1

https://search.asf.alaska.edu/#/

Also, this question:

https://www.researchgate.net/post/Where_can_I_download_free_DEMs_higher_than_30m_resolution_in_SE_ASIA_covering_the_Philippines

Dear Litesh Bopche

Most of DEM layers with resolution less than 10 m is not free and not cover all countries. however you can try this site:

https://earthexplorer.usgs.gov/

https://search.asf.alaska.edu/ (ALOS 12m resolution DSM data)

https://search.earthdata.nasa.gov/search (ASTER 30m resolution data)

To Download high quality DEM less than 5m will require you to purchase the DEM. And not country will be covered

It it important to be very specific about the location of your area of interest, and in the case of elevation data, provide perhaps the lat / longs of the bounding box - because, in general, the cost of acquiring and processing elevation data rises dramatically with the resolution. Also, the highest resolution data has military implications, so might be restricted in specific areas - but it can also be noted that permissions have been granted in certain cases, especially for archeological projects or relief efforts that only need limited areas. Also, there are derived datasets ( hydrology surveys ) and raw data collections ( aerial lidar surveys ) which can be repurposed depending on one's specific needs.

Also, sometimes one can process a lower resolution data set into a higher one if there is additional data that can be used for correction and processing techniques that preserve features like ridge lines and valleys. There are many special projects of specific use raw datasets which are not published for general consumption because of costs, for instance a river study might capture vast areas around the stream itself. Also, while the highest resolution commercial products are expensive, there are very inexpensive ones available at various resolutions.

Hi to follow this link

ALOS Polsar Data

https://search.asf.alaska.edu

Hi Litesh,

Mostly high accuracy DEMs are not available for free. You may generate one by field survey and GIS techniques if the study area is small.

Best wishes,

Dear Litesh Bopche I agree with others that high-quality DEM with less than 5-meter resolution is not available (free or purchased). It is also true that you can generate it for a small study area provided you have basic requirements to do so. We are mostly using the SRTM and ASTER-GDEM data for various kinds of research which are freely available from the websites. By saying this I don't rule out the existence of such data in any other part of the world. However, even if such data are available it may be highly restricted for public use.

Gibji Nimasow INRE: 'availability'. As noted in my previous post, being specific about the location and extents of the area of interest is paramount. For instance, the current USGS 3DEP elevation products ( https://www.usgs.gov/core-science-systems/ngp/3dep/3dep-product-availability-maps ) shown in my graphic were free, and are 1 meter with something like a 3 inch height error for a huge uninhabited area in the US. For my county in Puget Sound, we have Lidar point sets that show the picket fence in my yard. Much of the UK is available at 50cm ( https://data.gov.uk/dataset/5f6f7d5b-3f4c-4476-bfb8-cda490c9cf0e/lidar-composite-dtm-2017-50cm ). In other parts of the world, NGOs have also financed and distributed data, not mention academic scientific surveys.

In contrast, the Indian Survey data is extremely restrictive ( understandably so), but that may just require identifying gatekeepers and make a case why the restrictions should not apply, or finding a sponsor with access.

Even if a nice DEM isn't available, sometimes the underlying data for making your with an Open Source tool like Cloud Compare or MeshLab is available: https://www.usgs.gov/media/images/lidar-point-cloud-lpc-availability

Dear Michael John Patrick Thanks a lot for sharing the information. Yes, it is true that the Survey of India data is extremely restrictive.

Gibji Nimasow INRE: restrictions. After the 9/11 attacks in the U.S. there was an instinctive reaction to restrict practically all GIS data, because it might be used by terrorists and other potential threats. There was a commission convened with stakeholders from defense, EMS, utilities, etc. and in a very rare instance of government intelligence, it was decided that instead of classifying geospatial data, that the opposite should occur because of the critical needs of disaster response and coordinating the efforts of corporate, local, municipal, state, and federal agencies, and that actually more and better data should be accessible - that the benefit far exceeded and perceived benefit to malefactors who could easily find alternatives anyways.

Michael John Patrick Gibji Nimasow Jasem A Albanai Ismail Mondal Kehinde Gbola Adewuyi Karim Omar Samuel Akande Thank you all of you...

https://bhuvan-app3.nrsc.gov.in/data/download/index.php#