I gratefully acknowledge funding from the European Union through the GEO-C project (H2020-MSCA-ITN-2014, Grant Agreement Number 642332, http:// www.geo-c.eu); from the Citizen Science COST Action CA15212 www.cs-eu.net; and from the bursary provided by the Association of Geographic Information Laboratories in Europe -AGILE for gathering research data. I also acknowledge collaboration from the cyclists associations Castelló en Bici, B.A.G. Malta, and Critical Mass MS.