Co-written by Pedro Melhado, Igor Santana e Aline Graziadei

The goal of the YouthMappers UFBA’s Open Data Day event “Communities Mapping Communities: Brazil-Africa Connection” was to strengthen vulnerable communities in Brazil and Africa through the exchange of knowledge facilitated by open mapping data. Specific themes were addressed in three sessions directly linked to the following SDGs:

  • Session 1 – Kenya-Brazil Connection: Mapping for and with favelas, promoting community improvement interventions (SDGs 11 – Sustainable Cities and Communities and 17 – Partnerships for the Goals).
  • Session 2 – Mozambique-Brazil Connection: Use of open data for location and population estimation (SDGs 11 – Sustainable Cities and Communities and 17 – Partnerships for the Goals).
  • Session 3 – Bahia Connection: Mapping vulnerable urban areas promoting resilience to extreme events (SDGs 11 – Sustainable Cities and Communities and 13 – Climate Action).

The event comprised three days of seminars with 16 speakers from Brazil, Kenya, Mozambique, and the USA, two workshops, and one mapathon, including one hybrid day and two online days. All this was moderated by four graduate students members of our YouthMappers UFBA chapter, with the support of seven additional members directly involved in organizing the event. The complete program is available here.

We are very happy with the quality and numbers of the event which reveals its success: there were 75 registered participants, 58% undergraduates and 27% postgraduates. 35% of them were linked to the field of geography, with others from diverse areas such as Engineering (surveying and cartography, forestry, civil), Architecture and Urbanism, Veterinary Medicine, Epidemiology, Medicine, History, Geology, and High School). Most participants learned about the event through WhatsApp, colleagues, and professors.

On March 2nd, 18 people participated in person, including seven residents of the vulnerable community of Pau da Lima in Salvador, where mapping began on OSM during the mapathon on March 5th. A total of 52 certificates were issued for online or in-person participation in event activities.

For participants who filled out the seminar evaluation form, the event was very beneficial: 81% had a very positive evaluation (and 19% had a positive evaluation), highlighting the speakers, event themes, and interaction with people from the African continent. Regarding areas for improvement, 50% indicated that the timetable was not the best for them (we were limited to the morning due to differences in time zones with African countries), followed by event promotion that could be improved to reach more people. Over 90% intend to participate in the next edition of the event.

The Mapathon held, in one week, has already registered 3,532 edits in the project. But the area to be mapped is quite large, and we continue mapping!

The activities were recorded on the YouthMappers UFBA chapter’s YouTube channel and had 616 views just one week after the event!

The Youth Mappers UFBA chapter thanks everyone who participated in our Open Data Day event, whether by watching, asking questions, speaking, or promoting. We also thank the Polytechnic School of the Federal University of Bahia, the postgraduate programs PPEC and MAASA, and our supporters TOMTOM, the Humanitarian OpenStreetMap Team (HOT), and the Open Knowledge Foundation (OKFN)!

But the journey doesn’t end here! The cultural exchange activities between Brazil and Kenya, “Bringing Cultures Together through Open Mapping,” continue every other Saturday! Folks from the Community Mappers of Kibera (the largest favela in Africa) are getting in touch with the Portuguese language, while those from the social startup CommuniTech, from the Pau da Lima community (both from the outskirts of Salvador), and from the Community Mappers UFBA are getting acquainted with English! The inaugural workshop held during YouthMappers UFBA’s Open Data Day was inspiring, and this group will surely go very far!

About Open Data Day

Open Data Day (ODD) is an annual celebration of open data all over the world. Groups from many countries create local events on the day where they will use open data in their communities.

As a way to increase the representation of different cultures, since 2023 we offer the opportunity for organisations to host an Open Data Day event on the best date within a one-week period. In 2024, a total of 287 events happened all over the world between March 2nd-8th, in 60+ countries using 15 different languages.

All outputs are open for everyone to use and re-use.

In 2024, Open Data Day was also a part of the HOT OpenSummit ’23-24 initiative, a creative programme of global event collaborations that leverages experience, passion and connection to drive strong networks and collective action across the humanitarian open mapping movement

For more information, you can reach out to the Open Knowledge Foundation team by emailing You can also join the Open Data Day Google Group to ask for advice or share tips and get connected with others.