FAQ
All public administration data has been produced and/or acquired with Greek citizens’ money. So they belong to the Greek citizens and must be accessible to everyone without institutional or technical limitations. By ensuring that public administration data is open, we aid in:
- The effective control of public administration. Any public administration decision, permit, etc., relating to space, is based on law and information on location, i.e. geospatial data. If we all have access to this data, then we can check the correctness and validity of the decisions of the public sector.
- In environmental protection. By combining access to aerial and satellite images of the country with other geospatial data, such as protected areas, seashore, reforested areas, etc., each citizen can identify potential illegal acts and indicate them to the public administration.
- Decrease in resource waste by the public administration. Unfortunately even today the public administration as a whole does not know exactly what geospatial data are in its possession and has to reacquire them. Worse, many public bodies refuse to provide their geospatial data to other public sector entities.
- Improving competitiveness. Public administration data is useful for research, developing new products, improving services, reducing the cost of products and services, evaluating investments in the country, as well as many other areas.
The data offered by geodata.gov.gr is not just free, but open! The data are offered with the specific terms of Greek Creative Commons license Attribution (CC BY v.3.0) as specified in detail in the relevant License Use. This means that you can use them any way you want, improve them, edit them, create commercial applications, or anything else you wish. All you need to do is to indicate the source of origin, i.e. geodata.gov.gr.
In whatever you want! For each dataset in geodata.gov.gr you can choose to either download it in its original reference system, or any other that reference system you want! The transformation is done automatically and on demand by geodata.gov.gr.
It is good, however, to keep in mind the following points concerning the most common reference systems used in Greece.
GGRS87 is the National Reference System, as established by National Cadastre and Mapping Agency and used by all public administration sectors to manage geospatial data. Typically it provides better accuracy for the Greek territory and is used by all users of GIS in Greece.
WGS84 is a reference system generally used by all services you can find on the internet. This means that you can combine maps and data from multiple different open and free sources. Also, it is easier for a non-expert user to take advantage of geospatial data in simple applications, while specialists can easily make the transformation to another reference system.
OpenStreetMap is a collaborative effort to create global maps that are freely offered to everyone. Anyone can contribute in creating the maps, in a very simple way. For example, you can simply add the name of a road that does not exist, or fill out a new path.
We use OpenStreetMap for two reasons:
- It’s open and not just free.
- We believe in open data and we are trying to highlight their importance.
- Unfortunately there no other alternatives available
We invite you to help in the Greek community of OpenStreetMap !
Unfortunately geodata.gov.gr does not itself produce the geospatial data for Greece. Our role is to help the public sector in the opening of public information and ensure the availability of open data with the best technical resources, services and infrastructure.
So, if you do not find data that interest you, this means that the data is not offered openly from the public bodies that produce them.
How you can help?
- Take part in the public dialogue with public bodies which have the data, mobilize voluntary groups, local government, MPs, or any other organization or person who can help.
- Publicly explain with simple arguments why the missing data is useful for you, its importance to you and to others
- If you are a member of the public sector, please contact us to help you open your data. It is extremely simple, easy, fast and useful for citizens.
- For our part, for important datasets that are not openly offered by the public sector, we make sure to incorporate data from other sources in geodata.gov.gr.
Geospatial data files, such as text files you use everyday on your computer, require special software in order to view and use them. This software is called GIS (Geographic Information System) and is offered by many manufacturers, both as proprietary and as open source software. In addition, similarly to creating text files in different file formats depending on the software you are using (e.g., doc for Microsoft Word, odt for LibreOffice ), there are different formats for geospatial data files.
All geodata.gov.gr geospatial data files are offered in at least three equivalent formats that include the same information: SHP , GML , KML, in addition to many more!. So we ensure that the files of geodata.gov.gr be usable by all open and closed GIS applications. You will always have at least one free application that can use the data.
So how do I open the downloaded files?
You can use any of the open and closed GIS applications included in this list . Also, you can use Google Earth to open KML files. However, we recommend you use one of these free applications that are available for free:
First try to download the file again, as there is always the case for some problem incurring in the initial transfer. Then check the file size. If you see that it is bigger than a few tens of megabytes, then most likely you will not be able to open it with Google Earth. Unfortunately Google Earth is not a complete GIS system and for this reason we recommend you use one of the free applications that are mentioned above.
Most likely because the file is very large in size! In this case you need to import the file into a geospatial database (e.g., PostGIS ) and then connect to the database using a GIS software (e.g., QGIS ).
Unfortunately there is no easier way. Be aware that you need to know how to use a GIS or seek the help of a specialist. For this reason we make sure that all data in geodata.gov.gr is also available for previewing in the interactive maps , so that it is accessible to all!
Sometimes we receive questions from users about how to use the files they have downloaded. For example: « How can I find the distance between two schools; » or « How can I find the wind potential in my area; ». Unfortunately in these cases there is no easy way: you should have knowledge about the function of a GIS and its capabilities for querying geospatial data.
The previous version of geodata.gov.gr can be found at http://old.geodata.gov.gr, but keep in mind that the provided data might will not be updated. Any new open geospatial data will be added only on geodata.gov.gr.