This document describes a process for publishing spatial data as GeoLinked Data. The process involves: 1) Identifying data sources from the Spanish National Geographic Institute, 2) Developing an ontology to model the data, 3) Generating RDF data by mapping the relational databases to the ontology, and 4) Publishing and visualizing the data on the web. The goal is to enrich the web of data with Spanish geospatial information as part of an open data initiative. Future work includes improving data quality, linking to other datasets, and expanding into new domains.

1. An Approach to Publish Spatial Data
on the Web:
The GeoLinked Data Use Case
Luis M. Vilches-Blázquez, Boris Villazón-Terrazas, Alexander de León
Freddy Priyatna, and Oscar Corcho
Facultad de Informática, Universidad Politécnica de Madrid
Campus de Montegancedo sn, 28660 Boadilla del Monte, Madrid
http://www.oeg-upm.net
Phone: 34.91.3366605, Fax: 34.91.3524819

2. ToC
• Introduction
• A Process for Publishing GeoLinked Data
• Identification of the data sources
• Ontology modelling
• Generation of the RDF data
• Data publication and visualization
• Conclusions and Future Work

3. Introduction
• Open Data Movement and Web of Data.
• GeoLinkedData is an open initiative whose aim is to
enrich the Web of Data with Spanish geospatial data.
• It has started off by publishing diverse information
sources from the National Geographic Institute of
Spain (IGN).

4. A Process for Publishing GeoLinked Data
1. Identification
of the data sources
2. Ontology
modelling
3. Generation
of the RDF data
4. Data publication
and visualization

5. 1. Identification of the data sources
IGN
National Geographic Institute of Spain
Oracle & MySQL
All these data sources contain multilingual information
in the official languages of Spain (Castilian, Galician, Catalan, and Basque).

6. 2. Ontology modelling
• hydrOntology is an OWL-DL ontology that follows a top-down
development approach.
• It attempts to cover most of the concepts of the hydrographical
domain.
• Harmonizing heterogeneous information sources coming from
several cartographic agencies and other international resources.
• Regarding methodological issues, the approach adopted is
METHONTOLOGY, a widely-used ontology building methodology.
• Knowledge models (feature catalogues of the IGN, the Water
Framework European Directive, the Alexandria Digital Library, the
UNESCO Thesaurus, Getty Thesaurus, GeoNames, FACC codes,
etc.).
• It has 150 classes, 34 object properties, 66 data properties and 256
axioms.

7. 3. Generation of the RDF Data
• R2O is an extensible, fully declarative language to describe
mappings between relational database schemas and ontologies.
• The ODEMapster processor generates Semantic Web
instances from relational instances based on the mapping
description expressed in the R2O document.

8. 3. Generation of the RDF Data
• Creation of the R2O Mappings

9. 3. Generation of the RDF Data

10. 3. Generation of the RDF Data
Excerpt of the R2O document

11. 4. Data publication and visualization
HTML Linked Data SPARQL
Including Provenance
Support
Pubby
Pubby 0.3
Virtuoso 6.1.0

12. 4. Data publication and visualization
Metadata elements:
- Dublin Core
- voiD metadata

13. http://geo.linkeddata.es/

14. Provinces

15. Beaches

16. Conclusions and Future Work
• Conclusions
• An ongoing process aimed at publishing spatial data on the
Web with a Spanish GeoLinked Data use case
• The process followed and proposed methodological
guidelines for the involved activities.
• Future work
• Data cleansing
• Identifying and interlinking with DBpedia and Geonames
• Include other domains
• Improve faceted browser

18. An Approach to Publish Spatial Data
on the Web:
The GeoLinked Data Use Case
Luis M. Vilches-Blázquez, Boris Villazón-Terrazas, Alexander de León
Freddy Priyatna, and Oscar Corcho
Facultad de Informática, Universidad Politécnica de Madrid
Campus de Montegancedo sn, 28660 Boadilla del Monte, Madrid
http://www.oeg-upm.net
Phone: 34.91.3366605, Fax: 34.91.3524819