Geomorphometry 2021 - General Information

About Perugia

Perugia is the capital of the Umbria Region (the Green Heart of Italy), and is located in central Italy. The town is of Etruscan originand contains more than 160,000 inhabitants.

The Acropolis of Perugia (about 490 m a.s.l.) has been selected by the Etruscan people for the topographic arrangement on two contiguous hills, Colle del Sole and Colle Landone, and for the water resources.

The oldest urban center is enclosed by walls dating from the 3rd Century BC, that are themselves incorporated into a medieval fortification (14th Century).

The latter fortification encompasses the five villages (or districts) that have developed along the five main hill ridges towards the surrounding suburbs. This expansion took place in five directions, corresponding to the five Etruscan doors and has given the city a stellar shape that Renaissance architect Leon Battista Alberti compared to the fingers of a hand.

Its rich history is well represented by the works of art housed in the most representative cities, and the numerous monuments that characterize the urban profile of its historic center. Among these monuments is first and foremost the Fontana Maggiore, built in the 13th Century. After construction of the aqueduct through which water was channeled to the center of the city, and which is still accessible today. In the Piazza IV November there is the Cathedral of San Lorenzo, which was completed during the 15th Century. The Palazzo dei Priori built between the 14th and 16th Century, is now the Town Hall of the Municipality of Perugia, and contains the National Gallery of Umbria, the region’s most important museum. Here visitors can admire works of artists such as Pinturicchio, Perugino, Pietro della Francesca, Gentile da Fabriano, and other work of arts covering a time span between the 13th and 19th Century.

Among the many other architectural works worthy of mention is Rocca Paolina, a fortress built by Pope Paul III in 1540, at the end of the Salt War, in which Perugia fought against the Papal State imposing taxes on the importation of marine salt. Only one wing remains of this monumental building, designed by Sangallo the Younger, one of the greatest military engineers of the 16th Century. The area under the building, the major underground citadel, is still accessible, however, having become one of the symbols of the city. It is now crossed by a path of escalators leading from the main bus terminal up to the city center.

Perugia is the home of one of the oldest universities in Italy, founded in 1308, as attested by the Papal Bull issued by Pope Clement V certifying the birth of the Studium Generale. In addition to the University of Perugia is the University for Foreigners, founded in 1925, being the oldest university in Italy addressed to foreigners, and which specializes in the teaching and diffusion of the Italian language and culture worldwide.

In this highly suggestive scenario, and rich history, art and science surroundings, many cultural activities take place, making Perugia one of the most dynamic and attractive Italian cities. The best globally-known initiatives range from international music festivals (Umbria Jazz) to promotion of economic activities and crafts (UmbriaLibri), and from local confectionery production (Eurochocolate) to large conferences in the field of media and information (International Journalism Festival), and science (Perugia Science Fest or The Isle of Einstein).

Tourist guides

Reaching Perugia

Here you can find some information about how to reach Perugia and contacts of the major Italian transportation companies.

By Bus (from Rome-Fiumicino Airport to Perugia)

If you take the Sulga bus (www.sulga.it) from Rome-Fiumicino Airport, you will arrive at Piazza Partigiani, the bus station in the Perugia city center.

The bus station at the airport is located in the parking area in front of Terminal 3, arrivals level. To find the bus station (Sulga bus) to Perugia please go outside the arrival gate and walk to your right until the end of terminals, following the “Bus Station” sign. You should see a series of bus parking spaces. The Sulga buses to Perugia arrive at the bus stops 35 or 36

There is no timetable for the Sulga busses available at the Rome-Fiumicino Airport. Please check the latest timetable in advance:

Sulga Busses Service

The one-way bus fare from Rome-Fiumicino Airport to Perugia or vice versa is about € 22, and the roundtrip fare is about € 36 (valid for one month). The tickets can be purchased on board and by cash only or in advance on the Sulga website.

By train

Plese check the official website of TRENITALIA (National railways)

Telephone +39 075 5006186 www.trenitalia.com

By plane

San Francesco d’Assisi - Umbria International Airport - Perugia 12 km from Perugia Telephone +39 075 592141 www.airport.umbria.it

Amerigo Vespucci Airport - Florence 160 km from Perugia - 235 km from Terni Telephone +39 055 3061300 www.aeroporto.firenze.it

Leonardo da Vinci International Airport - Rome 210 km from Perugia - 120 km from Terni Telephone +39 06 65951 www.adr.it

Galileo Galilei Airport - Pisa 230 km from Perugia - 300 km from Terni Tel. +39 050 849300 www.pisa-airport.com

By car

A1 Motorway Florence-Rome Exits: Valdichiana (follow traffic signs for Terontola-Perugia junction), Chiusi-Chianciano, Orte(follow traffic signs for Perugia-Cesena), Attigliano, Orvieto, Fabro www.autostrade.it/en/index.html

A14 Motorway Bologna-Bari Arriving from the North, exits at Rimini (follow traffic signs for Città di Castello), Fano (follow traffic signs for Gubbio) Arriving from the South, exits at Ancona Nord (follow traffic signs for Gubbio), Pescara (follow traffic signs for Terni via L’Aquila-Rieti), Civitanova Marche (follow traffic signs for Foligno-Perugia) www.autostrade.it/en/index.html

Dual carriage-way E45 Cesena-Orte Crosses Umbria from top to bottom

COVID 19

We planned the 2021 edition of the conference to be a mixed in-person and online event.

We are working to understand if this is still allowed by the pandemic situation. The rule to participate in indoor activities in Italy, effective August 6th, is that a “green pass” (electronic certificate of full vaccination) is mandatory. Indoor activities include restaurants, cinemas, concerts and conferences. It looks like, effective September 1st, a “green pass” will also be necessary to travel by plane or train, but this is still under debate.

Please check this page for updates about the possibility of in-person attendance and upcoming regulations on this page. And please check with your country’s travelling regulations before making plans to travel to Italy.

For further information please refer to the institutional web page of the Italian Ministry of Health.

Latest Posts

DEMIX reveals which DEMs perform best

First round of the DEMIX exercise published final report

Global digital elevation models (DEMs) have become routine operational inputs across mapping, environmental monitoring, modelling and Earth-observation workflows. Their broad coverage and global availability have made them data that many practitioners simply take for granted. But knowledge of the terrain and topography of Earth’s surface is fundamental for monitoring and understanding terrestrial ecosystems and the planet’s habitability. For that reason, the CEOS Working Group on Calibration and Validation (WGCV) maintains a subgroup dedicated to digital topography and the quality of DEMs, the ‘Terrain Mapping Sub-Group (TMSG).

DEMs are representations of elevation in the form of a georectified grid, at global scale commonly derived from space-based interferometric synthetic aperture radar (InSAR) or stereoscopic optical observations, while regionally and locally airborne Laser induced detection and ranging (LIDAR) has become the primary source. DEMs can be classified as digital surface models (DSMs) when depicting the lower surface of the atmosphere or digital terrain models (DTMs) when depicting the top of the lithosphere (the Earth’s crust).

A wide variety of DEM products exist – each having different characteristics which suit different applications. It can be challenging to understand which of the available DEM products are fit for purpose for certain applications or regions. That is the practical gap addressed by the Digital Elevation Model Intercomparison Exercise (DEMIX) undertaken by TMSG. By exposing where widely used global DEMs agree, where they differ and how those differences affect rankings, the exercise delivered evidence to users for selecting a DEM rather than defaulting to one by habit.

DEM products were compared through a ‘wine contest,’ which identified requirements of openness, reproducibility, adaptability, and statistical rigour. The characteristics, evaluations, and ranking for each DEM were collected in a GIS database with over 50,000 entries. A quantitative assessment was carried out for each global DEM based on pixel-by-pixel differences of geomorphometric parameters against finer spatial resolution (1-5 m resolution) reference DEMs.

The study incorporates an unprecedented amount of high quality reference data covering a broad range of landforms and surface types, comparing their characteristics without resampling or interpolation. Users are invited to consult the results of DEMIX in order to make informed choices when needing to use a DEM, or in some cases a combination of the most relevant DEMs for their applications.

The final rankings of the wine contest, presented below, compared the six DEMs based on land cover (forest, urban, or barren), slope (cliff, steep, gentle, or flat), differences in elevation, slope and roughness, and statistical metrics.

Led by the European Commission’s Joint Research Centre (JRC), the CEOS Working Group on Calibration and Validation (WGCV) Terrain Mapping Subgroup (TMSG) established DEMIX in partnership with the International Society for Geomorphometry. Several members of the International Society of the Geomorphometry contributed significantly and we hosted various secssions at our latest conference. The exercise was performed over a three-year period starting in 2020, with community-wide calls for participation and an assembly of experts producing a number of peer-reviewed publications, culminating with a JRC reference report published in July 2026.

The objective of DEMIX was to propose a procedure to rank the available free and open global DEMs, taking into consideration user needs while promoting the implementation of FAIR (Findable, Accessible, Interoperable and Reusable) principles. The exercise compared DEMs based on criteria for land cover and terrain slope categories, representative testing, and a statistically sound ranking approach. The report outputs tailored recommendations regarding available DEM products that are not limited to one domain, geographic area, or landscape type, with flexibility for different user needs and applications.

A major challenge in the comparison of the global DEMs were the varying formats, data, and metadata contents. The adoption of a common set of standards would enhance the quality and interoperability of global DEMs and streamline the exchange and utilisation of DEM data for both providers and users. DEMIX makes the following recommendations for data providers:

● Adopt a standardised grid layout, with complete grid definitions and encodings following ISO/OGC rules.

● Include vertical datum information as part of raster DEM files.

● Clearly indicate the product version in the file names.

● Participate in future DEMIX rounds, which serve as a neutral platform for independently evaluating products before their release.

● Provide high quality, finer resolution, accurate, and multi-temporal elevation data to be used as a reference alongside DEM products.

Global DEMs are indispensable operational geospatial datasets, but they should not be treated as error-free or interchangeable. DEMIX delivered to the global community a systematic and transparent method to help choose elevation products more intelligently and help define what better elevation measurements should look like in the future.

Further Reading:

Read more in the DEMIX Final Report, or see other DEMIX publications below - mainly by our ISG members:

  • Benchmarking Elevation Plus Land Surface Parameters Finds FathomDEM and Copernicus DEM Win as Best Global DEMs (2025) and subsequent discussion (2026a, 2026b)
  • Ranking of 10 Global One-Arc-Second DEMs Reveals Limitations in Terrain Morphology Representation 2025
  • Novel Approach for Ranking DEMs: Copernicus DEM Improves One Arc Second Open Global Topography (2024)
  • Digital Elevation Models: Terminology and Definitions (2021)
  • The Digital Elevation Model Intercomparison eXperiment DEMIX, a community-based approach at global DEM benchmarking (2021)

Coffee Talk - GeoNadir

Building the world’s largest repository of FAIR drone mapping data

Paul Mead GeoNadir

September 2nd, 2026
11:30 (UTC)

Bio: Paul Mead is Co-founder and Head of Business & Strategy at GeoNadir, a platform building the world’s largest repository of FAIR drone mapping data to support environmental decision-making. A non-technical co-founder, Paul focuses on strategy, commercial development, and building high-performing teams — a discipline shaped by 11 years in the New Zealand Army, including leading a bomb disposal team in Lebanon and service in Afghanistan and the Asia-Pacific region. Since 2013 he has built and led several small businesses and start-ups, with drones as a central technology since 2016. Alongside GeoNadir, Paul co-founded She Maps, an internationally recognised drone and geospatial STEM education organisation, and has helped raise over $7M in equity and non-equity funding across his ventures. He holds a Master of Philosophy from the University of Queensland and is a Chartered Manager.

Abstract: GeoNadir set out to build the world’s largest repository of FAIR drone mapping data, and ended up building something more powerful. Drones have democratised data capture, but the same democratised ability to generate decision-grade insights from the data is lacking. I’ll walk through how we’re closing that gap: the data infrastructure behind hosting large volumes of UAV imagery and derived products, and how we’re moving from manual analysis toward automated, repeatable geospatial analytics.

Coffee Talk - Geomorphometry with GRASS

Geomorphometry with GRASS

Dr. Corey T. White Center for Geospatial Analytics at NCSU, USA

April 1st, 2026
14:00 (UTC)

Recording available in our YouTube channel

Bio: Corey White is a geospatial research software engineer with the Center for Geospatial Analytics at North Carolina State University and a maintainer of the open-source GRASS project. He is also the founder of OpenPlains Inc., an open-source web-based platform for interactive geospatial modeling. His work sits at the intersection of geomorphometry, environmental modeling, UAS mapping, and open-source software development, with a focus on making interactive terrain analysis accessible and reproducible. He has applied GRASS to problems ranging from post-disaster topographic change detection following Hurricane Helene to designing a participatory geospatial modeling platform to address ‘wicked’ socio-environmental problems. Corey is an active member of the OSGeo community and an advocate for open geospatial science.

Abstract: GRASS is a modern, actively developed, and extensible geospatial processing engine for geomorphometry. This session draws on post-Hurricane Helene landscape change analysis and ongoing addon development for DEM data fusion, terrain uncertainty modeling, and overland flow simulation to showcase what GRASS does well and where it fits in contemporary geomorphometric practice. Beyond its core analytical capabilities, GRASS’s Python, R, and Jupyter integration make it straightforward to build reproducible, scriptable terrain workflows that move easily from exploration to publication. Join this informal discussion to explore how GRASS serves not only as a research tool but as a community platform where geomorphometric methods can be developed, shared, and reused through its open addon ecosystem.